Orthodontic Maxillary Molar Movement-Induced Zygomatic Pillar Remodeling and its Consequences on Occlusal Characteristics and Stress Distribution

Orthodontic Maxillary Molar Movement-Induced Zygomatic Pillar Remodeling and its Consequences on Occlusal Characteristics and Stress Distribution | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Orthodontic Maxillary Molar Movement-Induced Zygomatic Pillar Remodeling and its Consequences on Occlusal Characteristics and Stress Distribution Size Li, Han Bao, Xiaojie Su, Liping Xiong, Qianwen Yin, Deao Gu, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3824244/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 15 Jun, 2024 Read the published version in Clinical Oral Investigations → Version 1 posted 9 You are reading this latest preprint version Abstract Objective : To evaluate zygomatic pillar changes during orthodontic treatment with premolar extraction, then analyze the effects of maxillary first molar movement on zygomatic pillar remodeling, and examine occlusal characteristics and stress distribution after reconstruction. Methods : 25 premolar extraction patients were included. Zygomatic pillar measurement range was defined, and cross-sectional areas, surface landmark coordinates, and alveolar and cortical bone thickness and density changes were assessed using Mimics based on the CBCT taken before(T0)and after treatment(T1). Multiple linear regression was employed to explain correlations between zygomatic pillar changes and maxillary first molar 3D movement and rotation. Correlations between pillar remodeling and occlusal characteristics, as analyzed by Tteester, were calculated. Pre- and post-reconstruction 3D finite element models (FEA) were constructed and loaded with average occlusal force of two period , respectively. Results : Zygomatic pillar cross-sectional area, landmark coordinates, bone thickness and alveolar bone density decreased. The mesial and lingual movement of the maxillary molars was strongly correlated with these changes, accounting for >40% variations. Occusal stress concentrated on weak areas after remodeling. Conclusions : Orthodontic treatment with premolar extraction led to zygomatic pillar remodeling, making it more fragile and reducing the occusal force of the maxillary first molar and the entire dentition with stress concentrating on weak areas. Clinical Relevance : No other study has focused on the effects of orthodontics on pillar structures.This research indicates that mesial movement of the maxillary first molar weakened zygomatic pillar, reduced occlusal function, and providing insights for insrting anchorage screws and facial aesthetics. Orthodontic treatment Zygomatic pillar Bone remodeing the Maxillary Molar Movement the Maximum occlusal force and occlusal contact area Finite element analysis Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 1 Introduction Orthodontic treatment is based on the biological principle that applying prolonged light forces to teeth results in tooth movement accompanied by remodeling of the surrounding bone [1] . Bone remodeling occurs not only in cancellous bone but also in cortical bone during this process, as demonstrated by researches [2] . The alveolar bone extends upward to the maxillary bone, dispersing the received forces throughout the skull. Sicher and colleagues proposed that three vertical pillars are formed in the maxillary bone by the thickening aggregation of bone along the direction of force transmission, namely the canine pillar, the zygomatic pillar, and the pterygoid pillar. These pillar structures, composed of alveolar bone and the cortical bone above, bear masticatory stress and external forces, providing optimal resistance scaffolding [3] . During the orthodontic process, forces on the teeth are also transmitted along the pillars. However, there are currently few studies investigating whether orthodontic treatment is accompanied by remodeling of the pillar structure. Of the three pillars, the zygomatic pillar bears the masticatory forces from the maxillary first molar, originates from its alveolar bone, and is bifurcated upwards via the zygomatic alveolar crest: one branch extends laterally from the orbital rim through the zygomatic process of the frontal bone to the skullcap, and the other branch extends posteriorly through the zygomatic arch to the skull base. Since the maxillary first molar plays a significant role in supporting occlusal forces as an essential component of the posterior dental support system [4–5] , the zygomatic pillar becomes one of the most resistant areas in the craniofacial bones [6] . Research shows that in orthodontic cases with extraction of premolars, even with maximum anchorage designed, the posterior teeth's movement accounts for approximately one-third of the extraction space [7] . Based on this phenomenon, ChoiDS [8] and others used three-dimensional finite element analysis on premolar extraction orthodontic models and found that tooth movement affects the stress distribution in the maxilla. According to Wolff's Law [9] in biomechanics, changes in the force applied to bones can cause changes in their internal structure and external morphology, such as bone density and thickness variations. During the premolar extraction orthodontic process, the starting position, force, and stress distribution of the zygomatic pillar changed, and the pillar's primary function is to handle occlusal forces. Research shows that patients undergoing premolar extraction treatment experience a decrease in occlusal forces. [10] Therefore, we further examine the remodeling of the zygomatic pillar structure extending upward from the maxillary first molar by observing the changes in occlusal forces resulting from the positional change of maxillary molars in premolar extraction orthodontic cases. Based on the adaptive perspective of anatomical structure remodeling and biomechanical transmission changes, we explore whether changes to the zygomatic pillar structure may impact molar stability and the balance of occlusal force reestablishment. 2 Materials and methods 2.1 Subjects Data on alveolar buccal bone Thicknesses [11] , bone density [12] and occlusal force [10] from previous studys on orthodontic treatment were used to calculate the sample size by Gpower (the difference of means and standard deviations are -0.5,±0.7mm, 349.15±90.79HU, 0±1N,significance level = 0.05, power = 0.80).This indicated that 18 samples would be needed to be able to reject the null hypothesis with a power of 80% and a type I error of 0.05. A total of 25 malocclusion patients (9 males and 16 females, with an average age of 24.5 years) treated at the Affiliated Stomatology Hospital of Nanjing Medical University from 2020 to 2021 were selected. This study was approved by the Bioethics Committee of the Affiliated Stomatology Hospital of Medical School,Nanjing University (Approval No. JX-2022-NL05).Inclusion criteria: (1) aged 18-35years old; (2) no history of orthodontic treatment; (3) diagnosed with skeletal Class I, Angle's Class I, dental crowding or bimaxillary protrusion, requiring more than 9mm for aligning and leveling and intrusion of anterior teeth; (4) aside from third molars, complete permanent dentition (no missing teeth, retained primary teeth, supernumerary teeth or malformed teeth), healthy tooth structure, and periodontal tissues; (5) adopted the orthodontic treatment strategy of extracting four first premolars; (6) essentially symmetrical jawbone development; (7) not designing TAD solutions such as micro-implants.Exclusion criteria: (1) patients receiving orthodontic-orthognathic combined treatment; (2) history of maxillofacial trauma, cyst, tumor, surgery, or cleft lip and palate; (3) history of periodontal disease, systemic disease, temporomandibular joint disorder, or diseases affecting bone metabolism and are using related medications All patients underwent treatment using Damon 3MXt standard torque brackets (Ormco, Glendora, CA) and buccal tubes on molars, following a specific archwire sequence:The maxillary teeth were bonded and aligned using a sequence of 0.012'', 0.014'', 0.016'', and 0.016'' * 0.022'' 0.018'' * 0.025'' nickel-titanium archwires, followed by 0.018'' * 0.025'' stainless-steel archwires as the main archwire. Subsequently, the maxillary canines underwent distalization.Molar anchorage design: The second molar is included in the treatment, and after 6-8 months of adequate alignment and leveling, the second molar is prepared for anchorage at an angle of 10-15°. The posterior teeth are tied together, and a two-step sliding method is used to close the extraction space, with some cases using an intermaxillary traction force of approximately 150g. The average treatment duration is 2.19±0.75 years. 2.2 CBCT 2.2.1 Radiographic analysis : CBCT images (NewTom VGi [QRsrl, Verona, Italy]) were taken before treatment (T0) and on the day of orthodontic appliance removal (T1). Images were imported into three-dimensional measurement software (Mimics Medical 21.0, Materialise, Belgium). The orbital-ear plane, the mid-sagittal plane, and the coronal plane perpendicular to both planes were used as three-dimensional reference planes. Pre-treatment (T0) and post-treatment (T1) craniofacial bone and teeth three-dimensional images were extracted, and landmark localization and index measurement were performed (Figure 1). Detailed operations are as follows: 2.2.2 Zygomatic pillar measurement range : To accurately assess the zygomatic pillar change after orthodontic tooth movement, external reference lines, constructed from stable skeletal structures, were used in the study to define range. (1) Coronal range(horizontal):between the IF plane and the buccal lateral margin (Figure 2).(2) Sagittal range:between the Or plane and TSZ plane(Figure 3). (3) Vertical range: between the fmt plane and the M1 plane .The fmt,FH ,DMF planes divide the vertical range of the zygomatic pillar into upper, middle, and lower segments. (Figure 4) Measure the morphological changes of the zygomatic pillar.Cross-sectional area measurement of the zygomatic pillar: Divide the lower segment into thirds and the middle segment into halves, resulting in seven height planes h1-h7 (Figure 5) 2.2.3 Zygomatic pillar morphological change s: Measure the changes in the cross-sectional area in seven stable height planes within the fixed pillar range before and after treatment to reflect the overall morphological changes of the zygomatic pillar (Figure 6). Surface morphology landmark measurement of the zygomatic pillar: Locate four landmarks in the zygomatic pillar area: △ZFF ,△ZP ,△ZM ,△EKM (Figure 7).In Mimics, overlay the pre and post-treatment 3D models of the same patient to assess the coordinate changes of the landmarks within the software's coordinate system, reflecting the surface morphological changes of the zygomatic pillar. (Figure 8) 2.2.4 Zygomatic pillar structural changes ：Measure the bone thickness and bone density of the zygomatic pillar. Based on Juliana F's study [11] , adjust the 3D window in the Mimics software (Figure 6), so that the axial slices and Cross sections were setted(Figure 9).In axial slices of the mesiobuccal and distobuccal root long axes of the maxillary first molar (MB, DB), the following variables were assessed. Alveolar bone area: At 3 mm, 6 mm, and 9 mm above the CEJ(heights H1-H3), measure the buccal alveolar bone thickness (BT) and buccal alveolar bone density (BMD) in Hounsfield units by creating a 1.0 mm² ellipse in the bone using Mimics (Figure 10). Cortical bone area: Heights H4 and H5 are defined at 2 mm and 4 mm above the root apex, respectively. H6-H8 are consistent with h5-h7. Measure cortical bone thickness and density using the same method. 2.2.5 Maxillary first molar 3D movement and rotation :Following the methods of Dai FF et 's [13] research, we established a coordinate system using a constant reference plane to measure, respectively, the changes in mesial-distal ,buccolingual, and vetical movement distances, mesial-distal angulation, and buccolingual angulation of the maxillary first molar. 2.3 Occlusal Characteristic and Occlusal Stress Distribution Analysis Additionally, we performed an occlusal analysis using the Teetester 3.4 Occlusal Analysis System (E-Motion Inc., China) (Fig 11). The patient was seated with the FH plane parallel to the floor, and the sensor was placed gently inside the patient's mouth. From the rest position to the intercuspal position (ICP), occlusal load characteristics were recorded. The process was repeated three times.For the measurements, when the total force of ICP reached 100%, the following data were recorded – TCA,TOF,TOF/TCA,First molar OF,OF ratio of first molar ,OF ratio of anterior teeth ,OF ratio of premolar(only bilateral second premolars recorded after treatment); OF ratio of molar. Following the research methods of Dong-Soon Choi [7] , our study differs in that we selected pre- and post-treatment CBCT data from a 23-year-old female patient to produce two three-dimensional (3D) finite element (FE) models of a human skull (T0, T1). Next, we applied the average combined forces obtained from our research before and after treatment on each tooth in both models, to maximally simulate the stress distribution of occlusal forces on the craniofacial bones before and after zygomatic pillar reconstruction. All reference planes and measurements with their respective abbreviations are described in the Table 1. Table1 Definitions of Reference planes, Variables and their Abbreviations Reference plane/Measurement Abbreviation Description Frankfurt Horizontal Plane FH plane Plane that passes through two points: the right and left Porion and the right and left Orbitale Infraorbital foramen Plane IF plane Plane that passes through the infraorbital foramen parallel to the mid-sagittal plane Infraorbital Plane Or plane Plane that passes through the the infraorbital point (Or) parallel to the coronal plane Temporal zygomatic suture Plane TZS plane Plane that passes through through the highest point of the temporal zygomatic suture (TZS) parallel to the coronal frontozygomatic suture Plane Maxillary first molar Plane fmt plane M1 plane Plane that passes through the lowest point of the frontozygomatic suture parallel to the FH plane Plane that passes through the midpoint of the buccal alveolar crest of the maxillary first molar before treatment parallel to the FH plane Oramen magnum Plane DFM plane Plane passes through the posterior margin of the foramen magnum is the DFM plane Cross-sectional area of the the zygomatic pillar h1-h7 area Cross-sectional area in seven height planes within the measurement range of the zygomatic pillar Morphological landmarks on the surface of zygomatic pillar ZFF Zygomaticofacial foramina ZP Zygomatic pominence point (The most outward-projecting point on the body of the zygoma) Buccal alveolar bone thickness Buccal alveolar bone density ZM Zygomaxillare point (The lowest point of the zygomatico-mandibular suture) EKM Buccal bony eminence at the root apex of the mesiobuccal root of the first molar MBT1-MBT3 DBT1-DBT3 Buccal alveolar bone thickness of mesiobuccal/ distalbuccal root measured between the facial aspect of the root to the facial aspect of the alveolar bone at H1-H8 MBbmd1-MBbmd3 DBbmd1-DBbmd3 The average buccal alveolar bone density of buccal alveolar bone mentioned above Cortical bone thickness MBT4-MBT8 DBT4-DBT8 Cortical bone thickness measured between the facial surface and the inner surface of the Cortical bone Cortical bone density MBbmd4-MBbmd8 DBbmd4-DBbmd8 The average buccal alveolar bone density of Cortical bone mentioned above Total occclusal force TOF Total occlusal force throughout the entire dental arch Total area of occlusal contact TCA Total occlusal contact Area throughout the entire dental arch Occlusal force per unit area TOF/TCA Occlusal force per unit area assumed First molar OF First molar OF Occlusal force of bilateral First maxillary molar Bilateral Measurement △bi- Total deferences of bilateral body measurement for item between Timepoint T1 and T0 Occlusal force ratio of OF ratio of The sum of the occlusal forces of tooth in the segment as a percentage of the total occlusal force 2.4 Statistical Analyses We performed statistical analysis using SPSS 26.0. Radiographic data were measured twice by the same doctor at different time points, with no statistically significant differences in the data (P>0.05). The intra-group consistency analysis showed an ICC >0.80. The average of the two measurements was taken. The t-test showed no statistically significant differences in the data for the same measurements on both sides of the patients, so the data from both sides of the same patient were combined for statistical analysis. The Shapiro-Wilks test was used to test whether the variables were normally distributed, and paired-sample t-test ( t ) or Wilcoxon rank-sum test ( w ) was used to compare the differences in each index before and after treatment. Pearson correlation analysis was employed, respectively, to assess the correlation between statistically significant zygomatic pillar reconstruction indices and the maxillary first molar movement and angular changes as well as the correlation with changes in occlusal characteristics. A multivariable linear regression model (MLS) was used to investigate the influence of maxillary first molar movement on zygomatic pillar reconstruction. Results were presented as`x±s or P50(P25，P75) w p value <0.05 was considered statistically significant. 3 Results 3.1 Remodeling in Zygomatic Pillar Morphology After treatment, the overall cross-sectional area demonstrated a decreasing trend(Table 2 ). In particular, the decrease in cross-sectional area at three height planes of the lower segment of the zygomatic pillar was statistically significant (P < 0.05), with more significant changes on the two height planes closer to the alveolar crest. These results indicate that the overall morphology of the lower part of the zygomatic pillar is reduced, and the reduction in the base pillar shape beneath the tooth crown, where orthodontic and occlusal forces act, is more significant (P < 0.001). The coordinates of the surface morphological landmarks ZP on the X and Y axis, and ZM on the Y axis, were significantly decreased, indicating that the ZP point moved inward and backward, while the ZM point moved backward(Table 3 ). The EKM point also experienced significant displacement as the maxillary first molar moves, shifting mesially, palatally, and downward. The aforementioned data suggested that after reduction orthodontics, the mid-section surface morphological landmarks (ZM, ZP) of the zygomatic pillar moved backward, the ZP point moved inward, the pillar shape at this location shifted backward, while the starting point of the pillar moved forward. Table 2 Comparison of cross-sectional area measurements at 7 heights of zygomatic pillar at T0 and T1 Area T0 T1 T0-T1 Z/t P h1a 29.81 ± 5.39 27.48 ± 5.91 1.64 ± 4.99 4.182 0.000 ** h2a 43.61 ± 6.11 40.96 ± 5.35 2.66 ± 4.14 4.530 0.000 ** h3a 62.55 ± 5.40 60.77 ± 6.29 1.78 ± 5.37 2.348 0.023 * h4a 61.53 ± 20.21 62.71 ± 18.53 1.18 ± 8.06 -1.04 0.305 h5a 162.17 ± 36.06 162.09 ± 34.34 0.09 ± 8.52 0.073 0.942 h6a 302.33 ± 70.55 300.90 ± 65.72 1.43 ± 28.54 0.353 0.725 h7a 121.35 ± 38.79 118.05 ± 38.84 3.30 ± 16.72 1.39 0.170 * P < 0.05, ** P < 0.01 Table 3 Comparison of zygomatic pillar landmarks at T0 and T1 Measurement T0 T1 T0-T1 t P ZFF X 50.53 ± 3.89 50.83 ± 3.71 0.30 ± 1.97 -1.08 0.285 Y 32.50 ± 5.87 32.20 ± 6.12 0.30 ± 1.97 -1.90 0.064 Z 16.59 ± 3.02 16.71 ± 3.33 0.12 ± 1.89 0.452 0.653 ZP X 54.93 ± 4.93 54.51 ± 4.74 0.42 ± 0.62 4.757 0.000 ** Y 30.37 ± 6.10 29.06 ± 6.63 1.31 ± 1.54 -6.095 0.000 ** Z 16.61 ± 2.92 16.74 ± 3.30 0.12 ± 1。93 -0.439 0.662 X 47.53 ± 5.34 47.64 ± 5.1 0.11 ± 1.5 -0.528 0.600 ZM Y 31.17 ± 5.50 29.67 ± 5.69 1.51 ± 1.39 -7.678 0.000 ** Z -7.74 ± 2.36 -7.66 ± 2.51 0.80 ± 1.24 -0.459 0.649 EKM X 30.07 ± 3.93 29.24 ± 3.92 0.83 ± 1.26 4.666 0.000 ** Y 32.25 ± 4.70 33.65 ± 4.66 -1.40 ± 0.488 20.258 0.000 ** Z -14.36 ± 1.68 -14.94 ± 1.66 0.58 ± 0.63 6.52 0.000 ** * P < 0.05, ** P < 0.01 Table 4 Comparison of the thickness and density of buccal alveolar bone of maxillary first molar at T0 and T1 Measurement T0 T1 T0-T1 t P MB H1BT 1.65 ± 0.78 1.45 ± 0.81 0.20 ± 0.65 2.201 0.033 H2BT 1.77 ± 0.80 1.25 ± 0.76 0.27 ± 0.68 6.404 0.000 ** H3BT 3.37 ± 1.68 2.69.37 0.68 ± 1.00 4.825 0.000 ** DB H1BT 2.49 ± 0.82 2.23 ± 0.78 0.26 ± 0.47 3.966 0.000 ** H2BT 2.29 ± 0.88 2.01 ± 0.80 0.28 ± 0.47 4.235 0.000 ** H3BT 3.55 ± 1.60 3.10 ± 1.05 0.73 ± 1.42 2.431 0.019 ** MB H1Bbmd 1015.26 ± 193.61 863.28 ± 155.44 152.09 ± 225.38 4.772 0.000 ** H2Bbmd 1109.85 ± 225.51 986.48 ± 211.89 123.37 ± 166.03 5.254 0.000 * H3Bbmd 1114.84 ± 122.56 1065.45 ± 118.38 49.36 ± 81.78 4.271 0.000 ** DB H1Bbmd 922.53 ± 144.52 807.95 ± 182.47 44.58 ± 157.34 5.149 0.000 ** H2Bbmd 975.82 ± 188.32 884.67 ± 194.21 4.26 ± 83.57 7.795 0.000 ** H3Bbmd 1115.88 ± 123.62 1084.21 ± 151.10 31.67 ± 103.45 2.165 0.035 * * P < 0.05, ** P < 0.01 Table 5 Comparison of the cortical bone thickness of the zygomatic pillar at T0 and T1 Measurement T0 T1 T1-T0 t P MB H4BT 3.25 ± 1.06 2.94 ± 1.06 0.30 ± 0.74 2.913 0.005 * H5BT 3.53 ± 0.76 3.23 ± 1.43 0.30 ± 1.00 2.138 0.03 * H6BT 3.52 ± 0.76 3.24 ± 0.80 0.28 ± 0.90 2.176 0.034 H7BT 4.72 ± 1.27 4.26 ± 1.26 0.47 ± .0.91 3.631 0.001 H8BT 5.39 ± 2.69 5.25 ± 2.39 0.14 ± 1.97 0.486 0.629 DB H4BT 2.51 ± 1.08 2.20 ± 1.07 0.31 ± 0.81 2.706 0.009 ** H5BT 2.78 ± 1.37 2.45 ± 1.39 0.33 ± 0.72 3.263 0.002 ** H6BT 2.80 ± 0.75 2.46 ± 0.81 0.34 ± 0.84 2.873 0.006 ** H7BT 4.01 ± 1.27 3.57 ± 1.27 0.45 ± 0.92 3.459 0.001 ** H8BT 6.52 ± 3.11 6.34 ± 2.97 0.18 ± 1.21 1.084 0.284 * P < 0.05, ** P < 0.01 Table 6 Comparison of the cortical bone density of the zygomatic pillar at T0 and T1 Measurement T0 T1 T0-T1 t P MB H4bmd 1072.532 ± 275.85 1090.22 ± 225.49 -17.69 ± 194.52 -0.643 0.523 H5bmd 1137.02 ± 250.06 1138.18 ± 226.32 -1.16 ± 184.83 -0.044 0.965 H6bmd 1183.84 ± 267.00 1111.77 ± 248.10 72.07 ± 279.88 1.82 0.075 H7bmd 1314.12 ± 373.96 1207.34 ± 510.54 106.79 ± 380.20 1.986 0.053 H8bmd 1331.23 ± 318.03 1296.05 ± 350.74 35.18 ± 317.30 0.784 0.437 DB H4bmd 977.85 ± 322.23 1058.97 ± 256.28 -81.12 ± 290.38 -1.975 0.054 H5bmd 1111.15 ± 239.53 1129.04 ± 238.23 -17.81 ± 127.94 -0.989 0.327 H6bmd 1096.11 ± 267.69 1101.68 ± 205.27 -5.57 ± 161.89 -0.243 0.809 H7bmd 1372.20 ± 241.83 1382.30 ± 351.23 -10.09 ± 357.35 -0.200 0.843 H8bmd 1424.17 ± 295.95 1370.24 ± 405.73 54.04 ± 494.04 0.774 0.443 * P < 0.05, ** P < 0.01 3.2 Remodeling in Zygomatic Pillar Structure Consistent with the changes in cross-sectional area of the pillar, both the alveolar bone thickness and bone density of the maxillary first molar in the zygomatic pillar region were reduced(Table 4 ). Compared to the apical 1/3 location, 9mm above the CEJ, the reconstruction at locations 3mm and 6mm above the CEJ were more significant(except MBT3) (p < 0.001). Since most cases have no bone structure at the H9 height of the coronal plane of the tooth axis, H9 data was not included in the statistics. The cortical bone thickness of the zygomatic pillar was significantly reduced except for the H8 level, but there were no statistically significant difference in cortical bone density(Table 5 – 6 ). Table 7 Changes of maxillary first molar displacement and angulation Measurement ‾x ± s P Measial movement 1.30 ± 0.78 0.001 * Palatal movment 0.64 ± 0.92 0.000 ** Extrusion 0.09 ± 0.17 0.000 ** Mesial tipping 1.11 ± 1.14 0.000 ** Palatal tipping 0.37 ± 0.82 0.001 * * P < 0.05, ** P < 0.001 3.3 Correlation between Maxillary First Molar Position,Angulation Changes and Zygomatic Pillar Remodeling with the Multivariate Lineral Regression Model The mean mesial movement, palatal movement ,extrusion distance, and mesial tipping ,palatal tipping degree of Maxillary First Molar were 1.30 ± 0.78mm,0.64 ± 0.92mm,0.09 ± 0.17mm, 1.11 ± 1.14°,0.37 ± 0.82°respectively(Table 7 ). Matched-pairs T-test demonstrated the movement and inclination changes were significantly different between T0 and T1. The results of the Pearson correlation test are shown in Fig. 12 , revealing a strong positive correlation between zygomatic pillar morphological stuctural changes and mesiodistal and lingual movement of the molars. Specifically, both △MBT4-7 and △DB4-7 showed a correlation > 0.7 with mesial movement. Interestingly, △MBT1, △DBT1, △MBbmd1, and △DBbmd3 were positively correlated with extrusion, while △MBT3 and △DBT3 were related to palatal inclination. The backward movement of the ZP and ZM landmarks is related to mesial movement, and the inward movement of the ZP is associated with lingual movement and palatal inclination. As these variables reflecting the reconstruction of pillar morphology and structure are related to distinct types of maxillary first molar movement, and based on the correlation results, as well as the fact that dependent variables and residuals essentially follow a normal distribution without outliers (Fig. 13 ), this study employed multiple stepwise linear regression to investigate the impact of Changes of maxillary first molar displacement and angulation on zygomatic pillar remodeling, including only significant dependent variables (Table 8 ). In this experiment, the regression models for changes in cortical bone thickness, landmark coordinates, and cross-sectional area of the middle and upper parts of the zygomatic pillar had adjusted R-squared values greater than 0.4, with some even surpassing 0.6. This suggests that over 40% of the changes in cortical bone thickness, landmark coordinates, and cross-sectional area could be explained by varying molar movements, indicating that maxillary first molar movement, particularly mesial and palatal movement, is an crucial factor contributing to zygomatic pillar reconstruction in patients undergoing reduction orthodontic treatment. Table 8 Multiple linear regression model Response Variable Model R 2 Adj.R 2 F P △ MBL1 0.079 + 1.374 extrusion 0.114 0.096 6.189 0.016 △ MBL2 -0.26 + 0.325 measial movement + 0.223 palatal movement 0.561 0.543 30.066 0.000 △ MBL3 0.742 + 0.593 palatal tipping-0.254 measial tipping 0.280 0.250 9.151 0.000 △ MBL4 -0.582 + 0.682 measial movement 0.524 0.514 7.264 0.000 △ MBL5 -0.852 + 0.727 measial movement + 0.333 palatal movement 0.644 0.626 42.513 0.000 △ MBL6 -0.612 + 0.521 measial movement + 0.332 palatal movement 0.527 0.507 26.213 0.000 △ MBL7 -0.685 + 0.888 measial movement 0.583 0.575 67.24 0.000 △ DBT1 0.144 + 1.305 extrusion 0.202 0.185 12.158 0.001 △ DBL2 0.109 + 0.249 palatal movement 0.234 0.218 14.664 0.000 △ DBL3 0.213 + 0.631 palatal movement 0.159 0.142 9.089 0.004 △ DBL4 -0.566 + 0.675 measial movement 0.422 0.410 17.951 0.000 △ DBL5 -0.524 + 0.662 measial movement 0.510 0.500 49.927 0.000 △ DBL6 -0.584 + 0.545 measial movement + 0.337 palatal movement 0.651 0.636 43.799 0.000 △ DBL7 -0.697 + 0.688measial movement + 0.256 palatal movement + 0.996extrusion 0.664 0.642 30.250 0.000 △ MBbmd1 13.173 + 706.41extrusion + 102.067 palatal tipping + 57.918 measial movement 0.445 0.409 12.295 0.000 △ MBbmd2 67.841 + 86.255 palatal movement 0.226 0.210 14.044 0.000 △ MBbmd3 14.386 + 54.378 palatal movement 0.371 0.358 28.292 0.000 △ DBbmd1 22.077 + 71.289 measial movement 0.125 0.107 6.849 0.012 △ DBbmd2 69.730 + 51.831 palatal movement 0.258 0.242 16.654 0.000 △ DBbmd3 -8.86 + 83.674 palatal movement − 35.778 palatal tipping 0.518 0.498 22.407 0.000 △ ZPX 0.089 + 0.384 palatal movement + 0.222 palatal tipping 0.491 0.469 22.675 0.000 △ ZPY -0.158 + 0.844 measial movement + 0.582 palatal movement 0.503 0.482 23.790 0.000 △ ZMY 0.297 + 0.564 measial movement + 0.656 palatal movement 0.465 0.442 20.429 0.000 △ h1area -2.621 + 3.067 palatal movement + 1.764 measial movement 0.611 0.595 36.937 0.000 △ h2area 0.782 + 2.911 palatal movement 0.415 0.402 23.655 0.000 △ h3area -1.361 + 2.742 palatal movement − 1.365 palatal tipping + 2.229 measial movement 0.636 0.612 26.603 0.000 * P < 0.05, ** P < 0.01 Table 9 Changes of occlusal characteristics Measurement T0 T1 Z/t p TOF(mm 2 ) 342.63 ± 73.07 287.63 ± 77.31 -3.01 0.000 * TOA(kg) 54.56 ± 7.32 251.40 ± 9.12 -6.12 0.008 ** TOF /TOA (N/ mm 2 ) 0.16 ± 0.03 0.18 ± 0.03 -5.76 0.000 ** First molar OF (N) 14.50 ± 2.56 13.57 ± 2.76 -3.69 0.035 * OF ratio of first molar (%) 35(22,31.35) 27(22,30.5) -0.56 0.576 ( w ) OF ratio of anterior teeth (%) 27.68 ± 8.41 36.16 ± 6.82 -3.25 0.000 ** OF ratio of premolar(%) 44.84 ± 9.70 17.86 ± 4.21 6.853 0.000 ** OF ratio of molar (%) 27.00(22.50,30.50) 45(41.00, 51.5) 4.374 0.000 ** ( w ) * P < 0.05, ** P < 0.01 3.4 Correlation of Occlusal Characteristics and zygomatic pillar remodeling As shown in the Table 9 , the total occlusal force, total occlusal area, and occlusal force of the first molar all decreased after reduction orthodontic treatment. However, the occlusal force per unit area and the proportion of anterior teeth occlusal force increased, while the proportion of anterior molar occlusal force decreased. Moreover, as illustrated in the Fig. 14 , the association between the thinning of cortical bone thickness in the middle and upper parts of the zygomatic pillar, reduction of alveolar bone density, and decrease in the cross-sectional area of the pillar becomes more apparent, with the increased occlusal force of the first molar showing a greater trend (r > 0.4). Furthermore, the reduction of alveolar bone density (except for △MBbmd1 and △DBbmd2) and the decrease in cross-sectional area were significantly positively correlated (r > 0.4) with the decline in the total force and total occlusal area, meaning that the reconstruction of the zygomatic pillar structure significantly affects occlusal force changes. 3.5 Occlusal Stress distribution in T0 and T1 As shown in Fig. 15 , following zygomatic pillar reconstruction, the stress concentration area in the zygomatic alveolar ridge and buccal alveolar bone is reduced, and the stress at the posterior margin of the orbit decreases. However, the stress in the zygomatic arch area behind the temporozygomatic suture and at the intersection of the vertical and horizontal edges of the zygomatic bone significantly increases. 4 Discussion In odontics, it is common knowledge that the maxillary first molar and its associating zygomatic pillar that bears its occlusal force are crucial, and this has led to the development of concepts such as key ridge. Over the years, researchers have extensively discussed the reconstruction of alveolar bone accompanying orthodontic tooth movement, but few have focused on the pillar structures involved in force transmission within the cranium . Therefore, this study focuses on the remodeling of the zygomatic pillar before and after treatment in patients undergoing orthodontics with premolar extraction , the effect of maxillary first molar movement on zygomatic pillar reconstruction, and further investigates the impact of pillar reconstruction on occlusal features and stress distribution of occlusal forces in the skull. Primarily, bone remodeling includes two parts: morphological reconstruction and structural reconstruction. Comparing the cross-sectional areas of zygomatic pillars within a constant-height plane, it was found that the cross-sectional area of the lower part of the zygomatic pillar significantly decreased, reflecting a shrinkage in the overall shape of the lower part of the zygomatic pillar. The surface morphology landmarks of the zygomatic pillar's middle section, ZM, and ZP, moved backward, and the ZP point moved medially. This phenomenon maybe associated with the pressure stress on the vertical direction of the zygomaticomaxillary suture and the transversal pressure on zygomatic body when first molar move forward [14] . The pressure may have caused bone resorption. At the same time, the EKM point moves mesially, palatally, and extends along with the maxillary first molar. This implies that the starting point of the zygomatic pillar moves with the maxillary first molar, while the middle and upper sections shift backward and medially. The alveolar bone thickness of the maxillary first molar significantly decreased, which is consistent with previous research with non-extraction patients [11] . Moreover, the cortical bone thickness at all height planes, except for the fmt plane, significantly decreased. FEA research might explain this phenomenon [14] . As the first molar undergoes orthodontic movement, the pressure stress area also moves forward, causing the anterior cortical bone to be more compressed, and osteoclasts become active, leading to bone resorption. Bone structural reconstruction as seen in the absorption of alveolar bone density is consistent with Chang, H 's study [12] . The absence of significant changes in the cortical bone density of the pillar indicates that structural reconstruction is mainly limited to the lower segment of the zygomatic pillar. It was found that mesial and lingual movements in reduction orthodontic treatment were most closely related to zygomatic pillar remodeling, followed by extusion and tipping. The MLR equation shows that 40% of cortical bone thickness change, coordinate change, and cross-sectional area change are caused by changes of molar movement, suggesting that the movement of the maxillary first molar, especially mesial and palatal movement, is an important cause for zygomatic pillar remodeling in reduction orthodontic treatment patients. Occlusal force decreases after zygomatic pillar remodeling. The overall occlusal force results are consistent with Yoon, W'sview [10] , and it was further found that the occusal force of maxillary first molar was lowered, and the force ratio of the anterior teeth increased. This is probably in accordance with the increased stress on the anterior pillar [14] . The study further investigated the impact of zygomatic pillar construction on occlusal force, discovering that the more prominent the pillar bone thickness, lower segment bone density, and landmark displacement, the greater the decreasing trend of the maxillary first molar occlusal force. It also affects the total occlusal force and occlusal area, which corresponds to the function of the zygomatic pillar in bearing occlusal forces. After orthodontic treatment with premolar extraction, the overall structure of the zygomatic pillar becomes weaker, leading to a significant decrease in the corresponding occlusal force that can be borne. The occlusal stress analysis of the three-dimensional finite element model after zygomatic pillar remodeling shows a difference compared to the simple tooth alignment model after extraction [8] : stress is concentrated in the weak areas of the zygomatic pillar (near the most convex point of the zygomatic arch and the area where the vertical and horizontal edges intersect), implying that the ability of these fracture-prone areas to withstand external force impact is further reduced, lowering the resistance of the zygomatic pillar. 4.1 Innovantion Our study delineated the measurement areas for the zygomatic pillar. Prior research has only qualitatively described the morphology of the zygomatic pillar but has not defined its scope, making it impossible to quantitatively compare the remodeling of the zygomatic pillar. Based on the definition of the zygomatic pillar, this study establishes reference planes for the measurement range by using landmarks on stable bone structures. As it is believed that the outermost boundary of the canine pillar is the IF plane [14 , 15] ., and the zygomatic arch region can serve as a stable area for three-dimensional overlap before and after orthodontics [16] , the transverse inner boundary is defined by the IF plane, and the final boundary of the sagittal range is the highest point of the zygomatic-temporal suture. Based on the composition of the pillar, pillar is divided into upper, middle, and lower segments, and the easily remodeled lower and middle sections near the starting point of force are further divided into three and two sections for measurement. This study subsequently assessed the impact of three-dimensional directional movement of the maxillary first molar on zygomatic pillar remodeling. Prior literature has only associated individual tooth movement indices with alveolar bone thickness and density remodeling [2,11] , Moreover, this study explained the degree of impact of different maxillary first molar movement modes on zygomatic pillar remodeling through linear regression equations, laying the groundwork for predicting zygomatic pillar remodeling. At the same time, this study, for the first time, constructed two three-dimensional finite element models of a patient's zygomatic pillar before and after orthodontic treatment with premolar extraction. The average occlusal force of the same group of patients before and after treatment was applied, respectively. These models simulate the occlusal force stress distribution before and after the remodeling of the zygomatic pillar to the greatest extent possible, further explaining the impact of zygomatic pillar remodeling on occlusal characteristics and stress distribution. 4.2 Clinical significance 4.2.1 Anchorage : How to control anchorage is an issue repeatedly explored by orthodontists. Particularly during reduction orthodontic treatment, the retraction of anterior teeth will inevitably generate counteracting forces of equal magnitude and opposite direction. When not using bone screws or other TAD devices, these reaction forces mainly affect the posterior teeth, and exceeding a certain threshold will cause the posterior teeth to move forward. When there is significant crowding and the space for anterior teeth retraction is large, we do not want the forward movement of the posterior teeth to consume the space. At the same time, this study also proved that the mesial movement of the molars is strongly related to the remodeling of the zygomatic pillar, which becomes another condition restricting the movement of the maxillary first molar. Based on this study, in our clinical practice, we should consider not only the allocation of space but also adopt methods such as "posterior teeth ligation," "two-step method," "posterior bending," and use transpalatal arch, TPA, etc., to control excessive mesial movement of the maxillary first molar to prevent significant decline in occlusal function due to zygomatic pillar remodeling. 4.2.2 Implant screw : The zygomatic alveolar ridge of the zygomatic pillar is a common implantation site for temporary maxillary anchorage devices due to its dense bone quality and relatively wide cortical bone thickness. Scholars found that the thickest area tends to be between second premolar andfirst molar, and it is generally the primary site to consider for implantation. The common implantation timing for anchorage screws is after the teeth are aligned and leveled, with their axes properly positioned. However, our research found that as the first molar moves forward, the bone cortex of the zygomatic pillar(including zygomatic crest ), which is a common implantation site for anchorage screws, becomes thinner. During the alignment and leveling process, the maxillary first molar may have moved forward, which could affect the effectiveness of the anchorage screw implantation. Consequently, by adding devices such as transpalatal arches, the forward movement of the maxillary first molar during the alignment and leveling phase can be inhibited, along with reducing the decrease in cortical bone thickness. Alternatively, changing the implantation site, such as placing it between teeth 6 and 7 or using palatal mini-implants, can help avoid this potential risk. Moreover, if the molar is still required to move forward during the gap closure process after the insertion of mini-implants, it may affect the stability of the implanted mini-implants, becoming a partial cause of their dislodgment. 4.2.3 Facial aesthetics: The remodeling findings of this study may also have implications for facial aesthetics, as it was found that as the first molar moves mesially and lingually, the zygomatic point moves inward and backward, and the zygomatic-sphenoid suture point moves backward. These negative changes in bony prominences may partly explain the negative changes in the soft tissues of the cheekbone and nasolabial groove observed in some patients after orthodontic treatment [18-19] , such as the phenomenon of "brace face" in Chinese female orthodontic patients. It is speculated that these facial changes may not be solely attributed to soft tissue remodeling but also involve bony prominences remodeling. Restricting the movement of the first molar may also offer the possibility to reduce the effect of "brace face." 4.2.4 Stabilization: Lastly, the weakened zygomatic pillar after remodeling, by affecting the magnitude and distribution of occlusal forces, may also have an impact on the stability of orthodontic treatment outcomes since 4.3 Limitation s The shortcomings of this study lie in the fact that it does not yet include research on the remodeling of the entire alveolar process at different stages of retention after orthodontic treatment completion. The stability of the zygomatic pillar during the retention period is also crucial for the long-term effectiveness of the orthodontic treatment since it was suggested that occlusal force may recover during the retention period. Therefore, there is a need to further expand the sample size and extend the follow-up observation time. 5 Conclusions During orthodontic treatment with premolar extraction, the 3D movement and angular changes of the maxillary first molar resulted in increased fragility of the zygomatic pillar structure and morphology. This remodeling contributed to reduced occusal force, with concentration in the weak areas of zygomatic pillar. Declarations Author contributions : The first draft of the manuscript was written by Size Li who is the first author of this article and completed the data acquisition, analysis of data, picture drawing and drafting the manuscript. The 3D finite element modeling and analysis were mainly completed by Han Bao. Data collection was jointly contributed to by Xiaojie Su, Liping Xiong, Qianwen Yin, and Deao Gu. Substantial assistance in the revision and editing of the manuscript was rendered by Leiying Miao. Conception and design of the study were proposed by Chao Liu .All authors read and approved the final manuscript. Funding : The study was partially supported by Key Project supported by Medical Science and Technology Development Foundation, Nanjing Department of Health under Grant, ZKX22055 and "2015"Cultivation Program for Reserve Talent s for Academic Leaders of Nanjing Stomatological School,Medical School of Nanjing Univeristy, 0223A210. Data availability : All data supporting the fndings of this study are available within the paper. Ethics approval and consent to participate : This study was approved by the Ethics Committee of the Affiliated Stomatology Hospital of Medical School,Nanjing University (Approval No. JX-2022-NL05). Written informed consent was obtained from all individual participants included in the study. Consent for publication : Informed permission for publication was acquired from all patients. Conflict of interests : The authors declare no competing interests. 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Cite Share Download PDF Status: Published Journal Publication published 15 Jun, 2024 Read the published version in Clinical Oral Investigations → Version 1 posted Editorial decision: Revision requested 18 Mar, 2024 Reviews received at journal 12 Mar, 2024 Reviewers agreed at journal 02 Feb, 2024 Reviews received at journal 25 Jan, 2024 Reviewers agreed at journal 19 Jan, 2024 Reviewers invited by journal 19 Jan, 2024 Submission checks completed at journal 10 Jan, 2024 Editor assigned by journal 10 Jan, 2024 First submitted to journal 30 Dec, 2023 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-3824244","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":266424009,"identity":"d229cf84-893f-4f2e-9f42-9b1c7a6713e8","order_by":0,"name":"Size Li","email":"","orcid":"","institution":"Department of Orthodontics, Nanjing Stomatological Hospital, Affiliated Stomatological Hospital of Medical School, Nanjing University","correspondingAuthor":false,"prefix":"","firstName":"Size","middleName":"","lastName":"Li","suffix":""},{"id":266424011,"identity":"0651cd69-9564-4bcb-a04d-7dbfdc921569","order_by":1,"name":"Han 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University","correspondingAuthor":true,"prefix":"","firstName":"Chao","middleName":"","lastName":"Liu","suffix":""}],"badges":[],"createdAt":"2023-12-30 14:44:12","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3824244/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3824244/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00784-024-05713-3","type":"published","date":"2024-06-15T15:18:38+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":49542309,"identity":"b281b429-b0d2-4e7e-b529-fca590590c2c","added_by":"auto","created_at":"2024-01-12 17:33:27","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":291475,"visible":true,"origin":"","legend":"\u003cp\u003eThree-dimensional models of craniomaxillofacial bone before and after extraction orthodontic treatment (T0, T1)\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-3824244/v1/5d4e70b63d100594c9498600.png"},{"id":49543269,"identity":"96982b7a-bead-4824-80a8-7c6d88549669","added_by":"auto","created_at":"2024-01-12 17:41:27","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":398168,"visible":true,"origin":"","legend":"\u003cp\u003eTransverse measurement range of zygomatic pillar\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-3824244/v1/500d275205698f42742f5e6f.png"},{"id":49542307,"identity":"289bbf33-c2f5-411c-a950-4e842f425bf9","added_by":"auto","created_at":"2024-01-12 17:33:27","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":317497,"visible":true,"origin":"","legend":"\u003cp\u003eSagittal measurement range of zygomatic pillar\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-3824244/v1/17405e59303cd9ecb7204dea.png"},{"id":49543270,"identity":"5fc6d9f0-3233-4de5-8813-a3e2788246f8","added_by":"auto","created_at":"2024-01-12 17:41:27","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":326957,"visible":true,"origin":"","legend":"\u003cp\u003eSagittal measurement range of zygomatic pillar\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-3824244/v1/054225a99ed64e016edcd833.png"},{"id":49542311,"identity":"938a631e-c952-411f-b97e-3bd1b31fc42e","added_by":"auto","created_at":"2024-01-12 17:33:27","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":310952,"visible":true,"origin":"","legend":"\u003cp\u003eSeven stable height planes\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-3824244/v1/4e94f9f9784fb6cfabe32009.png"},{"id":49542320,"identity":"17ed61ba-cbae-472e-8156-15ded6b131c2","added_by":"auto","created_at":"2024-01-12 17:33:27","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":226876,"visible":true,"origin":"","legend":"\u003cp\u003eCross-sectional area of zygomatic pillars in seven height planes (h1-h7）\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-3824244/v1/0dbe3ff818e19e103f41da58.png"},{"id":49542317,"identity":"2e4d7a72-4305-432e-80e9-748b76a2ac3b","added_by":"auto","created_at":"2024-01-12 17:33:27","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":420921,"visible":true,"origin":"","legend":"\u003cp\u003eZygomatic pillar surface morphology\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-3824244/v1/54e6782301f92ca2f196c5cf.png"},{"id":49542318,"identity":"77190a1f-ab77-4608-b8aa-f7d013c01257","added_by":"auto","created_at":"2024-01-12 17:33:27","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":396141,"visible":true,"origin":"","legend":"\u003cp\u003e3D models overlapped before and after extraction orthodontic\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-3824244/v1/b361d78efc924d07a90fd48c.png"},{"id":49545151,"identity":"11ae0463-39de-46f2-b3d6-3a8da29716f4","added_by":"auto","created_at":"2024-01-12 18:05:27","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":174396,"visible":true,"origin":"","legend":"\u003cp\u003eThree views of CBCT a. sagittal view b.cross setion c.axial slices\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-3824244/v1/4a0f87f66dc87adf70ecefc2.png"},{"id":49543271,"identity":"c42efa5a-c5f7-43f2-a022-9334ee70f504","added_by":"auto","created_at":"2024-01-12 17:41:27","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":204112,"visible":true,"origin":"","legend":"\u003cp\u003eMeasurement of bone thickness and bone mineral density of alveolar bone of maxillary first molar and cortical bone of zygomatic pillar (red ellipse : alveolar bone density; green ellipse : cortical bone density yellow line : bone thickness)\u003c/p\u003e","description":"","filename":"10.png","url":"https://assets-eu.researchsquare.com/files/rs-3824244/v1/a683dfb0c58e5e299105b138.png"},{"id":49542312,"identity":"bae7c12f-6841-4933-b892-b71fbc2c9cd8","added_by":"auto","created_at":"2024-01-12 17:33:27","extension":"png","order_by":11,"title":"Figure 11","display":"","copyAsset":false,"role":"figure","size":317052,"visible":true,"origin":"","legend":"\u003cp\u003eTeetester analysis images at T0 and T1\u003c/p\u003e","description":"","filename":"11.png","url":"https://assets-eu.researchsquare.com/files/rs-3824244/v1/dcc377f2ed39dcac0963144d.png"},{"id":49544496,"identity":"c5e3fc30-cef0-441b-814c-55c0a186190e","added_by":"auto","created_at":"2024-01-12 17:49:27","extension":"png","order_by":12,"title":"Figure 12","display":"","copyAsset":false,"role":"figure","size":102693,"visible":true,"origin":"","legend":"\u003cp\u003eCorrelation between maxillary first molar position,angulation changes and zygomatic pillar\u003c/p\u003e","description":"","filename":"12.png","url":"https://assets-eu.researchsquare.com/files/rs-3824244/v1/408fa56270461698a1588d38.png"},{"id":49544814,"identity":"32e78164-0c91-4e13-b75c-186e6b123f96","added_by":"auto","created_at":"2024-01-12 17:57:27","extension":"png","order_by":13,"title":"Figure 13","display":"","copyAsset":false,"role":"figure","size":215068,"visible":true,"origin":"","legend":"\u003cp\u003ethe resident distributipon of zygomatic pillar remodeling\u003c/p\u003e","description":"","filename":"13.png","url":"https://assets-eu.researchsquare.com/files/rs-3824244/v1/94fd309edd41a54aae8d1f73.png"},{"id":49543276,"identity":"d8943613-31d2-4695-aba5-068bb166f602","added_by":"auto","created_at":"2024-01-12 17:41:27","extension":"png","order_by":14,"title":"Figure 14","display":"","copyAsset":false,"role":"figure","size":113950,"visible":true,"origin":"","legend":"\u003cp\u003eCorrelation between zygomatic pillar remodeling and changes of occlusal characteristics\u003c/p\u003e","description":"","filename":"14.png","url":"https://assets-eu.researchsquare.com/files/rs-3824244/v1/45683e0f20c6a60c95a1ce0c.png"},{"id":49543275,"identity":"ffe13878-c3af-4d63-87e4-439908c69fdc","added_by":"auto","created_at":"2024-01-12 17:41:27","extension":"png","order_by":15,"title":"Figure 15","display":"","copyAsset":false,"role":"figure","size":373759,"visible":true,"origin":"","legend":"\u003cp\u003eStress distribution of occusal force on the T0 and T1 3D FE model (black frame: stress reduction area ;red frame: stress elevation area）\u003c/p\u003e","description":"","filename":"15.png","url":"https://assets-eu.researchsquare.com/files/rs-3824244/v1/8426a0c521a0c4b657efe03f.png"},{"id":58823474,"identity":"e285525c-05ba-4a1e-b33c-f12ab9c6f19a","added_by":"auto","created_at":"2024-06-21 17:00:04","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":5668152,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3824244/v1/50f83d61-da65-442d-89b4-13c7408260d4.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Orthodontic Maxillary Molar Movement-Induced Zygomatic Pillar Remodeling and its Consequences on Occlusal Characteristics and Stress Distribution","fulltext":[{"header":"1 Introduction","content":"\u003cp\u003eOrthodontic treatment is based on the biological principle that applying prolonged light forces to teeth results in tooth movement accompanied by remodeling of the surrounding bone\u003csup\u003e[1]\u003c/sup\u003e. Bone remodeling occurs not only in cancellous bone but also in cortical bone during this process, as demonstrated by researches\u003csup\u003e[2]\u003c/sup\u003e. The alveolar bone extends upward to the maxillary bone, dispersing the received forces throughout the skull. Sicher and colleagues proposed that three vertical pillars are formed in the maxillary bone by the thickening aggregation of bone along the direction of force transmission, namely the canine pillar, the zygomatic pillar, and the pterygoid pillar. These pillar structures, composed of alveolar bone and the cortical bone above, bear masticatory stress and external forces, providing optimal resistance scaffolding \u003csup\u003e[3]\u003c/sup\u003e. During the orthodontic process, forces on the teeth are also transmitted along the pillars. However, there are currently few studies investigating whether orthodontic treatment is accompanied by remodeling of the pillar structure.\u003c/p\u003e \u003cp\u003eOf the three pillars, the zygomatic pillar bears the masticatory forces from the maxillary first molar, originates from its alveolar bone, and is bifurcated upwards via the zygomatic alveolar crest: one branch extends laterally from the orbital rim through the zygomatic process of the frontal bone to the skullcap, and the other branch extends posteriorly through the zygomatic arch to the skull base. Since the maxillary first molar plays a significant role in supporting occlusal forces as an essential component of the posterior dental support system\u003csup\u003e[4\u0026ndash;5]\u003c/sup\u003e, the zygomatic pillar becomes one of the most resistant areas in the craniofacial bones \u003csup\u003e[6]\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eResearch shows that in orthodontic cases with extraction of premolars, even with maximum anchorage designed, the posterior teeth's movement accounts for approximately one-third of the extraction space \u003csup\u003e[7]\u003c/sup\u003e. Based on this phenomenon, ChoiDS\u003csup\u003e[8]\u003c/sup\u003eand others used three-dimensional finite element analysis on premolar extraction orthodontic models and found that tooth movement affects the stress distribution in the maxilla. According to Wolff's Law \u003csup\u003e[9]\u003c/sup\u003e in biomechanics, changes in the force applied to bones can cause changes in their internal structure and external morphology, such as bone density and thickness variations.\u003c/p\u003e \u003cp\u003eDuring the premolar extraction orthodontic process, the starting position, force, and stress distribution of the zygomatic pillar changed, and the pillar's primary function is to handle occlusal forces. Research shows that patients undergoing premolar extraction treatment experience a decrease in occlusal forces. \u003csup\u003e[10]\u003c/sup\u003eTherefore, we further examine the remodeling of the zygomatic pillar structure extending upward from the maxillary first molar by observing the changes in occlusal forces resulting from the positional change of maxillary molars in premolar extraction orthodontic cases. Based on the adaptive perspective of anatomical structure remodeling and biomechanical transmission changes, we explore whether changes to the zygomatic pillar structure may impact molar stability and the balance of occlusal force reestablishment.\u003c/p\u003e"},{"header":"2 Materials and methods","content":"\u003cp\u003e\u003cstrong\u003e2.1 Subjects\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData on alveolar buccal bone Thicknesses\u003csup\u003e[11]\u003c/sup\u003e , bone density\u003csup\u003e[12]\u003c/sup\u003e and occlusal force\u003csup\u003e[10]\u003c/sup\u003e from previous studys on orthodontic treatment were used to calculate the sample size by Gpower (the difference of means and standard deviations are -0.5,\u0026plusmn;0.7mm, 349.15\u0026plusmn;90.79HU, 0\u0026plusmn;1N,significance level = 0.05, power = 0.80).This indicated that 18 samples would be needed to be able to reject the null hypothesis with a power of 80% and a type I error of 0.05.\u003c/p\u003e\n\u003cp\u003eA total of 25 malocclusion patients (9 males and 16 females, with an average age of 24.5 years) treated at the Affiliated Stomatology Hospital of Nanjing Medical University from 2020 to 2021 were selected. This study was approved by the Bioethics Committee of the Affiliated Stomatology Hospital of Medical School,Nanjing University (Approval No. JX-2022-NL05).Inclusion criteria: (1) aged 18-35years old; (2) no history of orthodontic treatment; (3) diagnosed with skeletal Class I, Angle\u0026apos;s Class I, dental crowding or bimaxillary protrusion, requiring more than 9mm for aligning and leveling and intrusion of anterior teeth; (4) aside from third molars, complete permanent dentition (no missing teeth, retained primary teeth, supernumerary teeth or malformed teeth), healthy tooth structure, and periodontal tissues; (5) adopted the orthodontic treatment strategy of extracting four first premolars; (6) essentially symmetrical jawbone development; (7) not designing TAD solutions such as micro-implants.Exclusion criteria: (1) patients receiving orthodontic-orthognathic combined treatment; (2) history of maxillofacial trauma, cyst, tumor, surgery, or cleft lip and palate; (3) history of periodontal disease, systemic disease, temporomandibular joint disorder, or diseases affecting bone metabolism and are using related medications\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp;All patients underwent treatment using Damon 3MXt standard torque brackets (Ormco, Glendora, CA) and buccal tubes on molars, following a specific archwire sequence:The maxillary teeth were bonded and aligned using a sequence of 0.012\u0026apos;\u0026apos;, 0.014\u0026apos;\u0026apos;, 0.016\u0026apos;\u0026apos;, and 0.016\u0026apos;\u0026apos; * 0.022\u0026apos;\u0026apos; 0.018\u0026apos;\u0026apos; * 0.025\u0026apos;\u0026apos; nickel-titanium archwires, followed by 0.018\u0026apos;\u0026apos; * 0.025\u0026apos;\u0026apos; stainless-steel archwires as the main archwire. Subsequently, the maxillary canines underwent distalization.Molar anchorage design: The second molar is included in the treatment, and after 6-8 months of adequate alignment and leveling, the second molar is prepared for anchorage at an angle of 10-15\u0026deg;. The posterior teeth are tied together, and a two-step sliding method is used to close the extraction space, with some cases using an intermaxillary traction force of approximately 150g. The average treatment duration is 2.19\u0026plusmn;0.75 years.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.2 \u0026nbsp;CBCT\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.2.1 \u0026nbsp;Radiographic analysis\u003c/strong\u003e: CBCT images (NewTom VGi [QRsrl, Verona, Italy]) were taken before treatment (T0) and on the day of orthodontic appliance removal (T1). Images were imported into three-dimensional measurement software (Mimics Medical 21.0, Materialise, Belgium). The orbital-ear plane, the mid-sagittal plane, and the coronal plane perpendicular to both planes were used as three-dimensional reference planes. Pre-treatment (T0) and post-treatment (T1) craniofacial bone and teeth three-dimensional images were extracted, and landmark localization and index measurement were performed (Figure 1). Detailed operations are as follows:\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.2.2 \u0026nbsp;Zygomatic pillar measurement range\u003c/strong\u003e: To accurately assess the zygomatic pillar change after orthodontic tooth movement, external reference lines, constructed from stable skeletal structures, were used in the study to define range. (1) Coronal range(horizontal):between the IF plane and the buccal lateral margin (Figure 2).(2) Sagittal range:between the Or plane and TSZ plane(Figure 3). (3) Vertical range: between the fmt plane and the M1 plane .The fmt,FH ,DMF planes divide the vertical range of the zygomatic pillar into upper, middle, and lower segments. (Figure 4) Measure the morphological changes of the zygomatic pillar.Cross-sectional area measurement of the zygomatic pillar: Divide the lower segment into thirds and the middle segment into halves, resulting in seven height planes h1-h7 (Figure 5)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.2.3\u003c/strong\u003e \u0026nbsp;\u003cstrong\u003eZygomatic pillar morphological change\u003c/strong\u003es: Measure the changes in the cross-sectional area in seven stable height planes within the fixed pillar range before and after treatment to reflect the overall morphological changes of the zygomatic pillar (Figure 6). Surface morphology landmark measurement of the zygomatic pillar: Locate four landmarks in the zygomatic pillar area: △ZFF ,△ZP ,△ZM ,△EKM (Figure 7).In Mimics, overlay the pre and post-treatment 3D models of the same patient to assess the coordinate changes of the landmarks within the software\u0026apos;s coordinate system, reflecting the surface morphological changes of the zygomatic pillar. (Figure 8)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.2.4 \u0026nbsp;Zygomatic pillar structural changes\u003c/strong\u003e：Measure the bone thickness and bone density of the zygomatic pillar. Based on Juliana F\u0026apos;s study\u003csup\u003e[11]\u003c/sup\u003e, adjust the 3D window in the Mimics software (Figure 6), so that the axial slices and Cross sections were setted(Figure 9).In axial slices of the mesiobuccal and distobuccal root long axes of the maxillary first molar (MB, DB), the following variables were assessed. Alveolar bone area: At 3 mm, 6 mm, and 9 mm above the CEJ(heights H1-H3), measure the buccal alveolar bone thickness (BT) and buccal alveolar bone density (BMD) in Hounsfield units by creating a 1.0 mm\u0026sup2; ellipse in the bone using Mimics (Figure 10). Cortical bone area: Heights H4 and H5 are defined at 2 mm and 4 mm above the root apex, respectively. H6-H8 are consistent with h5-h7. Measure cortical bone thickness and density using the same method.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.2.5 \u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eMaxillary first molar 3D movement and rotation\u003c/strong\u003e :Following the methods of Dai FF et \u0026apos;s\u003csup\u003e[13]\u003c/sup\u003e research, we established a coordinate system using a constant reference plane to measure, respectively, the changes in mesial-distal ,buccolingual, and vetical movement distances, mesial-distal angulation, and buccolingual angulation of the maxillary first molar.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.3 \u0026nbsp;Occlusal Characteristic and Occlusal Stress Distribution Analysis\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAdditionally, we performed an occlusal analysis using the Teetester 3.4 Occlusal Analysis System (E-Motion Inc., China) (Fig 11). The patient was seated with the FH plane parallel to the floor, and the sensor was placed gently inside the patient\u0026apos;s mouth. From the rest position to the intercuspal position (ICP), occlusal load characteristics were recorded. The process was repeated three times.For the measurements, when the total force of ICP reached 100%, the following data were recorded \u0026ndash; TCA,TOF,TOF/TCA,First molar OF,OF ratio of first molar\u0026nbsp;,OF ratio of anterior teeth ,OF ratio of premolar(only bilateral second premolars recorded after treatment); OF ratio of molar.\u003c/p\u003e\n\u003cp\u003eFollowing the research methods of Dong-Soon Choi\u003csup\u003e[7]\u003c/sup\u003e, our study differs in that we selected pre- and post-treatment CBCT data from a 23-year-old female patient to produce two three-dimensional (3D) finite element (FE) models of a human skull (T0, T1). Next, we applied the average combined forces obtained from our research before and after treatment on each tooth in both models, to maximally simulate the stress distribution of occlusal forces on the craniofacial bones before and after zygomatic pillar reconstruction. All reference planes and measurements with their respective abbreviations are described in the Table 1.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable1\u003c/strong\u003e\u0026nbsp; Definitions of Reference planes, Variables and their Abbreviations\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"99%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eReference plane/Measurement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eAbbreviation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003eDescription\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eFrankfurt Horizontal Plane\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eFH\u0026nbsp;plane\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003ePlane that passes through two points: the right and left Porion \u0026nbsp;and the right and left Orbitale\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eInfraorbital foramen Plane\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eIF plane\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003ePlane that\u0026nbsp;passes through the infraorbital foramen\u0026nbsp;parallel to the mid-sagittal plane\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eInfraorbital Plane\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eOr plane\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003ePlane that\u0026nbsp;passes through the the infraorbital point (Or)\u0026nbsp;parallel to the coronal plane\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eTemporal zygomatic suture Plane\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eTZS plane\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003ePlane that\u0026nbsp;passes through through the highest point of the temporal zygomatic suture (TZS)\u0026nbsp;parallel to the coronal\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003efrontozygomatic suture Plane\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eMaxillary first molar Plane\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003efmt plane\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eM1 plane\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003ePlane that passes through the lowest point of the frontozygomatic suture parallel to the FH plane\u0026nbsp;\u003c/p\u003e\n \u003cp\u003ePlane that\u0026nbsp;passes through the midpoint of the buccal alveolar crest of the maxillary first molar before treatment parallel to the FH plane\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eOramen magnum Plane\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eDFM plane\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003ePlane passes through the posterior margin of the foramen magnum is the DFM plane\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eCross-sectional area of the the zygomatic pillar\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eh1-h7\u0026nbsp;area\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003eCross-sectional area in seven height planes within the \u0026nbsp; \u0026nbsp; \u0026nbsp;measurement range of the zygomatic pillar\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003eMorphological landmarks on the surface of zygomatic pillar\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eZFF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003eZygomaticofacial \u0026nbsp;foramina\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"34.24657534246575%\" valign=\"top\"\u003e\n \u003cp\u003eZP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"65.75342465753425%\" valign=\"top\"\u003e\n \u003cp\u003eZygomatic pominence point (The most outward-projecting point on the body of the zygoma)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" rowspan=\"4\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eBuccal alveolar bone thickness\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eBuccal alveolar bone density\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eZM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003eZygomaxillare point (The\u0026nbsp;lowest point of the zygomatico-mandibular suture)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"34.24657534246575%\" valign=\"top\"\u003e\n \u003cp\u003eEKM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"65.75342465753425%\" valign=\"top\"\u003e\n \u003cp\u003eBuccal bony eminence at the root apex of the mesiobuccal root of the first molar\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"34.24657534246575%\" valign=\"top\"\u003e\n \u003cp\u003eMBT1-MBT3\u003c/p\u003e\n \u003cp\u003eDBT1-DBT3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"65.75342465753425%\" valign=\"top\"\u003e\n \u003cp\u003eBuccal alveolar bone thickness of mesiobuccal/ distalbuccal root measured between the facial aspect of the root to the facial\u0026nbsp;aspect of the alveolar bone at H1-H8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"34.24657534246575%\" valign=\"top\"\u003e\n \u003cp\u003eMBbmd1-MBbmd3\u003c/p\u003e\n \u003cp\u003eDBbmd1-DBbmd3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"65.75342465753425%\" valign=\"top\"\u003e\n \u003cp\u003eThe average buccal alveolar bone density of \u0026nbsp;buccal alveolar bone mentioned above\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eCortical bone thickness\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eMBT4-MBT8\u003c/p\u003e\n \u003cp\u003eDBT4-DBT8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003eCortical bone thickness measured between the facial surface and the inner surface of the Cortical bone\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eCortical bone density\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eMBbmd4-MBbmd8\u003c/p\u003e\n \u003cp\u003eDBbmd4-DBbmd8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003eThe average buccal alveolar bone density of Cortical bone mentioned above\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eTotal\u0026nbsp;occclusal force\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eTOF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003eTotal\u0026nbsp;occlusal force\u0026nbsp;throughout the\u0026nbsp;entire\u0026nbsp;dental\u0026nbsp;arch\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eTotal\u0026nbsp;area of occlusal contact\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eTCA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003eTotal\u0026nbsp;occlusal\u0026nbsp;contact Area\u0026nbsp;throughout the\u0026nbsp;entire\u0026nbsp;dental\u0026nbsp;arch\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eOcclusal force per unit area\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eTOF/TCA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003eOcclusal force per unit area assumed\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eFirst molar OF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eFirst molar OF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003eOcclusal force of bilateral First maxillary molar\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eBilateral \u0026nbsp;Measurement\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003e△bi-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003eTotal deferences of bilateral body measurement for\u0026nbsp;item between Timepoint T1 and T0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eOcclusal force ratio of\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.510204081632654%\" valign=\"top\"\u003e\n \u003cp\u003eOF ratio of\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"48.97959183673469%\" valign=\"top\"\u003e\n \u003cp\u003eThe sum of the occlusal forces of tooth in the segment as a percentage of the total occlusal force\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e2.4 \u0026nbsp;Statistical Analyses\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe performed statistical analysis using SPSS 26.0. Radiographic data were measured twice by the same doctor at different time points, with no statistically significant differences in the data (P\u0026gt;0.05). The intra-group consistency analysis showed an ICC \u0026gt;0.80. The average of the two measurements was taken. The t-test showed no statistically significant differences in the data for the same measurements on both sides of the patients, so the data from both sides of the same patient were combined for statistical analysis. The Shapiro-Wilks test was used to test whether the variables were normally distributed, and paired-sample t-test (\u003csup\u003et\u003c/sup\u003e) or Wilcoxon rank-sum test (\u003csup\u003ew\u003c/sup\u003e) was used to compare the differences in each index before and after treatment.\u003c/p\u003e\n\u003cp\u003ePearson correlation analysis was employed, respectively, to assess the correlation between statistically significant zygomatic pillar reconstruction indices and the maxillary first molar movement and angular changes as well as the correlation with changes in occlusal characteristics. A multivariable linear regression model (MLS) was used to investigate the influence of maxillary first molar movement on zygomatic pillar reconstruction. Results were presented as`x\u0026plusmn;s or P50(P25，P75)\u003csup\u003ew\u0026nbsp;\u003c/sup\u003ep value \u0026lt;0.05 was considered statistically significant.\u003c/p\u003e"},{"header":"3 Results","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n \u003ch2\u003e3.1 Remodeling in Zygomatic Pillar Morphology\u003c/h2\u003e\n \u003cp\u003eAfter treatment, the overall cross-sectional area demonstrated a decreasing trend(Table \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e). In particular, the decrease in cross-sectional area at three height planes of the lower segment of the zygomatic pillar was statistically significant (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05), with more significant changes on the two height planes closer to the alveolar crest. These results indicate that the overall morphology of the lower part of the zygomatic pillar is reduced, and the reduction in the base pillar shape beneath the tooth crown, where orthodontic and occlusal forces act, is more significant (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e\n \u003cp\u003eThe coordinates of the surface morphological landmarks ZP on the X and Y axis, and ZM on the Y axis, were significantly decreased, indicating that the ZP point moved inward and backward, while the ZM point moved backward(Table \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e). The EKM point also experienced significant displacement as the maxillary first molar moves, shifting mesially, palatally, and downward. The aforementioned data suggested that after reduction orthodontics, the mid-section surface morphological landmarks (ZM, ZP) of the zygomatic pillar moved backward, the ZP point moved inward, the pillar shape at this location shifted backward, while the starting point of the pillar moved forward.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eComparison of cross-sectional area measurements at 7 heights of zygomatic pillar at T0 and T1\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"6\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eArea\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eT0\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eT1\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eT0-T1\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eZ/t\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eh1a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e29.81\u0026thinsp;\u0026plusmn;\u0026thinsp;5.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e27.48\u0026thinsp;\u0026plusmn;\u0026thinsp;5.91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.64\u0026thinsp;\u0026plusmn;\u0026thinsp;4.99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4.182\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eh2a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e43.61\u0026thinsp;\u0026plusmn;\u0026thinsp;6.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e40.96\u0026thinsp;\u0026plusmn;\u0026thinsp;5.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.66\u0026thinsp;\u0026plusmn;\u0026thinsp;4.14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4.530\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eh3a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e62.55\u0026thinsp;\u0026plusmn;\u0026thinsp;5.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e60.77\u0026thinsp;\u0026plusmn;\u0026thinsp;6.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.78\u0026thinsp;\u0026plusmn;\u0026thinsp;5.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.348\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.023\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eh4a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e61.53\u0026thinsp;\u0026plusmn;\u0026thinsp;20.21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e62.71\u0026thinsp;\u0026plusmn;\u0026thinsp;18.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.18\u0026thinsp;\u0026plusmn;\u0026thinsp;8.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-1.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.305\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eh5a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e162.17\u0026thinsp;\u0026plusmn;\u0026thinsp;36.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e162.09\u0026thinsp;\u0026plusmn;\u0026thinsp;34.34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.09\u0026thinsp;\u0026plusmn;\u0026thinsp;8.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.073\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.942\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eh6a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e302.33\u0026thinsp;\u0026plusmn;\u0026thinsp;70.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e300.90\u0026thinsp;\u0026plusmn;\u0026thinsp;65.72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.43\u0026thinsp;\u0026plusmn;\u0026thinsp;28.54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.353\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.725\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eh7a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e121.35\u0026thinsp;\u0026plusmn;\u0026thinsp;38.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e118.05\u0026thinsp;\u0026plusmn;\u0026thinsp;38.84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.30\u0026thinsp;\u0026plusmn;\u0026thinsp;16.72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.170\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e\u003csup\u003e*\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.05, \u003csup\u003e**\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.01\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv align=\"left\" class=\"colspec\"\u003e\u003cbr\u003e\u003c/div\u003e\u0026nbsp;\u003ctable id=\"Tab3\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eComparison of zygomatic pillar landmarks at T0 and T1\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"9\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eMeasurement\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eT0\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eT1\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eT0-T1\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003et\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"1\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eZFF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eX\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e50.53\u0026thinsp;\u0026plusmn;\u0026thinsp;3.89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e50.83\u0026thinsp;\u0026plusmn;\u0026thinsp;3.71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.30\u0026thinsp;\u0026plusmn;\u0026thinsp;1.97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-1.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.285\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e32.50\u0026thinsp;\u0026plusmn;\u0026thinsp;5.87\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e32.20\u0026thinsp;\u0026plusmn;\u0026thinsp;6.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.30\u0026thinsp;\u0026plusmn;\u0026thinsp;1.97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-1.90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.064\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eZ\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16.59\u0026thinsp;\u0026plusmn;\u0026thinsp;3.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16.71\u0026thinsp;\u0026plusmn;\u0026thinsp;3.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.12\u0026thinsp;\u0026plusmn;\u0026thinsp;1.89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.452\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.653\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eZP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eX\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e54.93\u0026thinsp;\u0026plusmn;\u0026thinsp;4.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e54.51\u0026thinsp;\u0026plusmn;\u0026thinsp;4.74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.42\u0026thinsp;\u0026plusmn;\u0026thinsp;0.62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e4.757\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e30.37\u0026thinsp;\u0026plusmn;\u0026thinsp;6.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e29.06\u0026thinsp;\u0026plusmn;\u0026thinsp;6.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.31\u0026thinsp;\u0026plusmn;\u0026thinsp;1.54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-6.095\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eZ\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16.61\u0026thinsp;\u0026plusmn;\u0026thinsp;2.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16.74\u0026thinsp;\u0026plusmn;\u0026thinsp;3.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.12\u0026thinsp;\u0026plusmn;\u0026thinsp;1。93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-0.439\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.662\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eX\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e47.53\u0026thinsp;\u0026plusmn;\u0026thinsp;5.34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e47.64\u0026thinsp;\u0026plusmn;\u0026thinsp;5.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.11\u0026thinsp;\u0026plusmn;\u0026thinsp;1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-0.528\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.600\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eZM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e31.17\u0026thinsp;\u0026plusmn;\u0026thinsp;5.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e29.67\u0026thinsp;\u0026plusmn;\u0026thinsp;5.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.51\u0026thinsp;\u0026plusmn;\u0026thinsp;1.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-7.678\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eZ\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-7.74\u0026thinsp;\u0026plusmn;\u0026thinsp;2.36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-7.66\u0026thinsp;\u0026plusmn;\u0026thinsp;2.51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.80\u0026thinsp;\u0026plusmn;\u0026thinsp;1.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-0.459\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.649\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eEKM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eX\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e30.07\u0026thinsp;\u0026plusmn;\u0026thinsp;3.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e29.24\u0026thinsp;\u0026plusmn;\u0026thinsp;3.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.83\u0026thinsp;\u0026plusmn;\u0026thinsp;1.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e4.666\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e32.25\u0026thinsp;\u0026plusmn;\u0026thinsp;4.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e33.65\u0026thinsp;\u0026plusmn;\u0026thinsp;4.66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-1.40\u0026thinsp;\u0026plusmn;\u0026thinsp;0.488\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e20.258\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eZ\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-14.36\u0026thinsp;\u0026plusmn;\u0026thinsp;1.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-14.94\u0026thinsp;\u0026plusmn;\u0026thinsp;1.66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.58\u0026thinsp;\u0026plusmn;\u0026thinsp;0.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e6.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"9\"\u003e\u003csup\u003e*\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.05, \u003csup\u003e**\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.01\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv align=\"left\" class=\"colspec\"\u003e\u003cbr\u003e\u003c/div\u003e\u0026nbsp;\u003ctable id=\"Tab4\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eComparison of the thickness and density of buccal alveolar bone of maxillary first molar at T0 and T1\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"9\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eMeasurement\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eT0\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eT1\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eT0-T1\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003et\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"1\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eMB\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH1BT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.65\u0026thinsp;\u0026plusmn;\u0026thinsp;0.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e1.45\u0026thinsp;\u0026plusmn;\u0026thinsp;0.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.20\u0026thinsp;\u0026plusmn;\u0026thinsp;0.65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.201\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.033\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH2BT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.77\u0026thinsp;\u0026plusmn;\u0026thinsp;0.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e1.25\u0026thinsp;\u0026plusmn;\u0026thinsp;0.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.27\u0026thinsp;\u0026plusmn;\u0026thinsp;0.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.404\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH3BT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.37\u0026thinsp;\u0026plusmn;\u0026thinsp;1.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e2.69.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.68\u0026thinsp;\u0026plusmn;\u0026thinsp;1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.825\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eDB\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH1BT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.49\u0026thinsp;\u0026plusmn;\u0026thinsp;0.82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e2.23\u0026thinsp;\u0026plusmn;\u0026thinsp;0.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.26\u0026thinsp;\u0026plusmn;\u0026thinsp;0.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.966\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH2BT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.29\u0026thinsp;\u0026plusmn;\u0026thinsp;0.88\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e2.01\u0026thinsp;\u0026plusmn;\u0026thinsp;0.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.28\u0026thinsp;\u0026plusmn;\u0026thinsp;0.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.235\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH3BT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.55\u0026thinsp;\u0026plusmn;\u0026thinsp;1.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e3.10\u0026thinsp;\u0026plusmn;\u0026thinsp;1.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.73\u0026thinsp;\u0026plusmn;\u0026thinsp;1.42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.431\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.019\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eMB\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH1Bbmd\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1015.26\u0026thinsp;\u0026plusmn;\u0026thinsp;193.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e863.28\u0026thinsp;\u0026plusmn;\u0026thinsp;155.44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e152.09\u0026thinsp;\u0026plusmn;\u0026thinsp;225.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.772\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH2Bbmd\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1109.85\u0026thinsp;\u0026plusmn;\u0026thinsp;225.51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e986.48\u0026thinsp;\u0026plusmn;\u0026thinsp;211.89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e123.37\u0026thinsp;\u0026plusmn;\u0026thinsp;166.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.254\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.000\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH3Bbmd\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1114.84\u0026thinsp;\u0026plusmn;\u0026thinsp;122.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e1065.45\u0026thinsp;\u0026plusmn;\u0026thinsp;118.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e49.36\u0026thinsp;\u0026plusmn;\u0026thinsp;81.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.271\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eDB\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH1Bbmd\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e922.53\u0026thinsp;\u0026plusmn;\u0026thinsp;144.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e807.95\u0026thinsp;\u0026plusmn;\u0026thinsp;182.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e44.58\u0026thinsp;\u0026plusmn;\u0026thinsp;157.34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.149\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH2Bbmd\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e975.82\u0026thinsp;\u0026plusmn;\u0026thinsp;188.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e884.67\u0026thinsp;\u0026plusmn;\u0026thinsp;194.21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.26\u0026thinsp;\u0026plusmn;\u0026thinsp;83.57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7.795\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH3Bbmd\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1115.88\u0026thinsp;\u0026plusmn;\u0026thinsp;123.62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e1084.21\u0026thinsp;\u0026plusmn;\u0026thinsp;151.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e31.67\u0026thinsp;\u0026plusmn;\u0026thinsp;103.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.165\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.035\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"9\"\u003e\u003csup\u003e*\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.05, \u003csup\u003e**\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.01\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv align=\"left\" class=\"colspec\"\u003e\u003cbr\u003e\u003c/div\u003e\u0026nbsp;\u003ctable id=\"Tab5\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eComparison of the cortical bone thickness of the zygomatic pillar at T0 and T1\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"8\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eMeasurement\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eT0\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eT1\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eT1-T0\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003et\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"1\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"5\"\u003e\n \u003cp\u003eMB\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH4BT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.25\u0026thinsp;\u0026plusmn;\u0026thinsp;1.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.94\u0026thinsp;\u0026plusmn;\u0026thinsp;1.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.30\u0026thinsp;\u0026plusmn;\u0026thinsp;0.74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.913\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.005\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH5BT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.53\u0026thinsp;\u0026plusmn;\u0026thinsp;0.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.23\u0026thinsp;\u0026plusmn;\u0026thinsp;1.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.30\u0026thinsp;\u0026plusmn;\u0026thinsp;1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.138\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.03\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH6BT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.52\u0026thinsp;\u0026plusmn;\u0026thinsp;0.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.24\u0026thinsp;\u0026plusmn;\u0026thinsp;0.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.28\u0026thinsp;\u0026plusmn;\u0026thinsp;0.90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.176\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.034\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH7BT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.72\u0026thinsp;\u0026plusmn;\u0026thinsp;1.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.26\u0026thinsp;\u0026plusmn;\u0026thinsp;1.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.47\u0026thinsp;\u0026plusmn;\u0026thinsp;.0.91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.631\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH8BT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.39\u0026thinsp;\u0026plusmn;\u0026thinsp;2.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.25\u0026thinsp;\u0026plusmn;\u0026thinsp;2.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.14\u0026thinsp;\u0026plusmn;\u0026thinsp;1.97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.486\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.629\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"5\"\u003e\n \u003cp\u003eDB\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH4BT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.51\u0026thinsp;\u0026plusmn;\u0026thinsp;1.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.20\u0026thinsp;\u0026plusmn;\u0026thinsp;1.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.31\u0026thinsp;\u0026plusmn;\u0026thinsp;0.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.706\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.009\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH5BT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.78\u0026thinsp;\u0026plusmn;\u0026thinsp;1.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.45\u0026thinsp;\u0026plusmn;\u0026thinsp;1.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.33\u0026thinsp;\u0026plusmn;\u0026thinsp;0.72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.263\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.002\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH6BT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.80\u0026thinsp;\u0026plusmn;\u0026thinsp;0.75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.46\u0026thinsp;\u0026plusmn;\u0026thinsp;0.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.34\u0026thinsp;\u0026plusmn;\u0026thinsp;0.84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.873\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.006\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH7BT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.01\u0026thinsp;\u0026plusmn;\u0026thinsp;1.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.57\u0026thinsp;\u0026plusmn;\u0026thinsp;1.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.45\u0026thinsp;\u0026plusmn;\u0026thinsp;0.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.459\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.001\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH8BT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.52\u0026thinsp;\u0026plusmn;\u0026thinsp;3.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.34\u0026thinsp;\u0026plusmn;\u0026thinsp;2.97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.18\u0026thinsp;\u0026plusmn;\u0026thinsp;1.21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.084\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.284\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"8\"\u003e\u003csup\u003e*\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.05, \u003csup\u003e**\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.01\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv align=\"left\" class=\"colspec\"\u003e\u003cbr\u003e\u003c/div\u003e\u0026nbsp;\u003ctable id=\"Tab6\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eComparison of the cortical bone density of the zygomatic pillar at T0 and T1\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"13\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003eMeasurement\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eT0\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eT1\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eT0-T1\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003et\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"1\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"5\"\u003e\n \u003cp\u003eMB\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH4bmd\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e1072.532\u0026thinsp;\u0026plusmn;\u0026thinsp;275.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e1090.22\u0026thinsp;\u0026plusmn;\u0026thinsp;225.49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-17.69\u0026thinsp;\u0026plusmn;\u0026thinsp;194.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-0.643\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.523\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH5bmd\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e1137.02\u0026thinsp;\u0026plusmn;\u0026thinsp;250.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e1138.18\u0026thinsp;\u0026plusmn;\u0026thinsp;226.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-1.16\u0026thinsp;\u0026plusmn;\u0026thinsp;184.83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-0.044\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.965\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH6bmd\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e1183.84\u0026thinsp;\u0026plusmn;\u0026thinsp;267.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e1111.77\u0026thinsp;\u0026plusmn;\u0026thinsp;248.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e72.07\u0026thinsp;\u0026plusmn;\u0026thinsp;279.88\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e1.82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.075\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH7bmd\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e1314.12\u0026thinsp;\u0026plusmn;\u0026thinsp;373.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e1207.34\u0026thinsp;\u0026plusmn;\u0026thinsp;510.54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e106.79\u0026thinsp;\u0026plusmn;\u0026thinsp;380.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e1.986\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.053\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH8bmd\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e1331.23\u0026thinsp;\u0026plusmn;\u0026thinsp;318.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e1296.05\u0026thinsp;\u0026plusmn;\u0026thinsp;350.74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e35.18\u0026thinsp;\u0026plusmn;\u0026thinsp;317.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.784\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.437\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"5\"\u003e\n \u003cp\u003eDB\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH4bmd\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e977.85\u0026thinsp;\u0026plusmn;\u0026thinsp;322.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e1058.97\u0026thinsp;\u0026plusmn;\u0026thinsp;256.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-81.12\u0026thinsp;\u0026plusmn;\u0026thinsp;290.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-1.975\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.054\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH5bmd\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e1111.15\u0026thinsp;\u0026plusmn;\u0026thinsp;239.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e1129.04\u0026thinsp;\u0026plusmn;\u0026thinsp;238.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-17.81\u0026thinsp;\u0026plusmn;\u0026thinsp;127.94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-0.989\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.327\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH6bmd\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e1096.11\u0026thinsp;\u0026plusmn;\u0026thinsp;267.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e1101.68\u0026thinsp;\u0026plusmn;\u0026thinsp;205.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-5.57\u0026thinsp;\u0026plusmn;\u0026thinsp;161.89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-0.243\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.809\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH7bmd\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e1372.20\u0026thinsp;\u0026plusmn;\u0026thinsp;241.83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e1382.30\u0026thinsp;\u0026plusmn;\u0026thinsp;351.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-10.09\u0026thinsp;\u0026plusmn;\u0026thinsp;357.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e-0.200\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.843\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH8bmd\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e1424.17\u0026thinsp;\u0026plusmn;\u0026thinsp;295.95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e1370.24\u0026thinsp;\u0026plusmn;\u0026thinsp;405.73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e54.04\u0026thinsp;\u0026plusmn;\u0026thinsp;494.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.774\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.443\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"13\"\u003e\u003csup\u003e*\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.05, \u003csup\u003e**\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.01\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e\n \u003ch2\u003e3.2 Remodeling in Zygomatic Pillar Structure\u003c/h2\u003e\n \u003cp\u003eConsistent with the changes in cross-sectional area of the pillar, both the alveolar bone thickness and bone density of the maxillary first molar in the zygomatic pillar region were reduced(Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e). Compared to the apical 1/3 location, 9mm above the CEJ, the reconstruction at locations 3mm and 6mm above the CEJ were more significant(except MBT3) (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv align=\"left\" class=\"colspec\"\u003eSince most cases have no bone structure at the H9 height of the coronal plane of the tooth axis, H9 data was not included in the statistics. The cortical bone thickness of the zygomatic pillar was significantly reduced except for the H8 level, but there were no statistically significant difference in cortical bone density(Table \u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e).\u003c/div\u003e\n \u003c/div\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab8\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 7\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eChanges of maxillary first molar displacement and angulation\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"3\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMeasurement\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u0026oline;x\u0026thinsp;\u0026plusmn;\u0026thinsp;s\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMeasial movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.30\u0026thinsp;\u0026plusmn;\u0026thinsp;0.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.001\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePalatal movment\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.64\u0026thinsp;\u0026plusmn;\u0026thinsp;0.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eExtrusion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.09\u0026thinsp;\u0026plusmn;\u0026thinsp;0.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMesial tipping\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.11\u0026thinsp;\u0026plusmn;\u0026thinsp;1.14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePalatal tipping\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.37\u0026thinsp;\u0026plusmn;\u0026thinsp;0.82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.001\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"3\"\u003e\u003csup\u003e*\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.05, \u003csup\u003e**\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.001\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003e\u003cstrong\u003e3.3 Correlation between Maxillary First Molar Position,Angulation Changes and Zygomatic Pillar Remodeling with the Multivariate Lineral Regression Model\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003eThe mean mesial movement, palatal movement ,extrusion distance, and mesial tipping ,palatal tipping degree of Maxillary First Molar were 1.30\u0026thinsp;\u0026plusmn;\u0026thinsp;0.78mm,0.64\u0026thinsp;\u0026plusmn;\u0026thinsp;0.92mm,0.09\u0026thinsp;\u0026plusmn;\u0026thinsp;0.17mm, 1.11\u0026thinsp;\u0026plusmn;\u0026thinsp;1.14\u0026deg;,0.37\u0026thinsp;\u0026plusmn;\u0026thinsp;0.82\u0026deg;respectively(Table \u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003e). Matched-pairs T-test demonstrated the movement and inclination changes were significantly different between T0 and T1.\u003c/p\u003e\n \u003cp\u003eThe results of the Pearson correlation test are shown in Fig. \u003cspan class=\"InternalRef\"\u003e12\u003c/span\u003e, revealing a strong positive correlation between zygomatic pillar morphological stuctural changes and mesiodistal and lingual movement of the molars. Specifically, both △MBT4-7 and △DB4-7 showed a correlation\u0026thinsp;\u0026gt;\u0026thinsp;0.7 with mesial movement. Interestingly, △MBT1, △DBT1, △MBbmd1, and △DBbmd3 were positively correlated with extrusion, while △MBT3 and △DBT3 were related to palatal inclination. The backward movement of the ZP and ZM landmarks is related to mesial movement, and the inward movement of the ZP is associated with lingual movement and palatal inclination.\u003c/p\u003e\n \u003cp\u003eAs these variables reflecting the reconstruction of pillar morphology and structure are related to distinct types of maxillary first molar movement, and based on the correlation results, as well as the fact that dependent variables and residuals essentially follow a normal distribution without outliers (Fig. \u003cspan class=\"InternalRef\"\u003e13\u003c/span\u003e), this study employed multiple stepwise linear regression to investigate the impact of Changes of maxillary first molar displacement and angulation on zygomatic pillar remodeling, including only significant dependent variables (Table \u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e). In this experiment, the regression models for changes in cortical bone thickness, landmark coordinates, and cross-sectional area of the middle and upper parts of the zygomatic pillar had adjusted R-squared values greater than 0.4, with some even surpassing 0.6. This suggests that over 40% of the changes in cortical bone thickness, landmark coordinates, and cross-sectional area could be explained by varying molar movements, indicating that maxillary first molar movement, particularly mesial and palatal movement, is an crucial factor contributing to zygomatic pillar reconstruction in patients undergoing reduction orthodontic treatment.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab9\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 8\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eMultiple linear regression model\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"6\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eResponse\u003c/p\u003e\n \u003cp\u003eVariable\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eModel\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eR\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAdj.R\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eF\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ MBL1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.079\u0026thinsp;+\u0026thinsp;1.374 extrusion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.114\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.096\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.189\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.016\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ MBL2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.26\u0026thinsp;+\u0026thinsp;0.325 measial movement\u0026thinsp;+\u0026thinsp;0.223 palatal movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.561\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.543\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e30.066\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ MBL3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.742\u0026thinsp;+\u0026thinsp;0.593 palatal tipping-0.254 measial tipping\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.280\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.250\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9.151\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ MBL4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.582\u0026thinsp;+\u0026thinsp;0.682 measial movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.524\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.514\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7.264\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ MBL5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.852\u0026thinsp;+\u0026thinsp;0.727 measial movement\u0026thinsp;+\u0026thinsp;0.333 palatal movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.644\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.626\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e42.513\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ MBL6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.612\u0026thinsp;+\u0026thinsp;0.521 measial movement\u0026thinsp;+\u0026thinsp;0.332 palatal movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.527\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.507\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e26.213\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ MBL7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.685\u0026thinsp;+\u0026thinsp;0.888 measial movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.583\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.575\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e67.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ DBT1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.144\u0026thinsp;+\u0026thinsp;1.305 extrusion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.202\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.185\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12.158\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ DBL2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.109\u0026thinsp;+\u0026thinsp;0.249 palatal movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.234\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.218\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14.664\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ DBL3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.213\u0026thinsp;+\u0026thinsp;0.631 palatal movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.159\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.142\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9.089\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.004\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ DBL4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.566\u0026thinsp;+\u0026thinsp;0.675 measial movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.422\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.410\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17.951\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ DBL5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.524\u0026thinsp;+\u0026thinsp;0.662 measial movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.510\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.500\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e49.927\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ DBL6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.584\u0026thinsp;+\u0026thinsp;0.545 measial movement\u0026thinsp;+\u0026thinsp;0.337 palatal movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.651\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.636\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e43.799\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ DBL7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.697\u0026thinsp;+\u0026thinsp;0.688measial movement\u0026thinsp;+\u0026thinsp;0.256 palatal movement\u0026thinsp;+\u0026thinsp;0.996extrusion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.664\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.642\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e30.250\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ MBbmd1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13.173\u0026thinsp;+\u0026thinsp;706.41extrusion\u0026thinsp;+\u0026thinsp;102.067 palatal tipping\u0026thinsp;+\u0026thinsp;57.918 measial movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.445\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.409\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12.295\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ MBbmd2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e67.841\u0026thinsp;+\u0026thinsp;86.255 palatal movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.226\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.210\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14.044\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ MBbmd3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14.386\u0026thinsp;+\u0026thinsp;54.378 palatal movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.371\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.358\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e28.292\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ DBbmd1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e22.077\u0026thinsp;+\u0026thinsp;71.289 measial movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.125\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.107\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.849\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.012\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ DBbmd2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e69.730\u0026thinsp;+\u0026thinsp;51.831 palatal movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.258\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.242\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16.654\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ DBbmd3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-8.86\u0026thinsp;+\u0026thinsp;83.674 palatal movement \u0026minus;\u0026thinsp;35.778 palatal tipping\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.518\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.498\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e22.407\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ ZPX\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.089\u0026thinsp;+\u0026thinsp;0.384 palatal movement\u0026thinsp;+\u0026thinsp;0.222 palatal tipping\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.491\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.469\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e22.675\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ ZPY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.158\u0026thinsp;+\u0026thinsp;0.844 measial movement\u0026thinsp;+\u0026thinsp;0.582 palatal movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.503\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.482\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e23.790\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ ZMY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.297\u0026thinsp;+\u0026thinsp;0.564 measial movement\u0026thinsp;+\u0026thinsp;0.656 palatal movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.465\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.442\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20.429\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ h1area\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-2.621\u0026thinsp;+\u0026thinsp;3.067 palatal movement\u0026thinsp;+\u0026thinsp;1.764 measial movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.611\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.595\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e36.937\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ h2area\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.782\u0026thinsp;+\u0026thinsp;2.911 palatal movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.415\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.402\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e23.655\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e△ h3area\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-1.361\u0026thinsp;+\u0026thinsp;2.742 palatal movement \u0026minus;\u0026thinsp;1.365 palatal tipping\u0026thinsp;+\u0026thinsp;2.229 measial movement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.636\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.612\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e26.603\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e\u003csup\u003e*\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.05, \u003csup\u003e**\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.01\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv align=\"left\" class=\"colspec\"\u003e\u003cbr\u003e\u003c/div\u003e\u0026nbsp;\u003ctable id=\"Tab10\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 9\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eChanges of occlusal characteristics\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"6\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMeasurement\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eT0\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eT1\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eZ/t\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ep\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTOF(mm\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e342.63\u0026thinsp;\u0026plusmn;\u0026thinsp;73.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e287.63\u0026thinsp;\u0026plusmn;\u0026thinsp;77.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-3.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTOA(kg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e54.56\u0026thinsp;\u0026plusmn;\u0026thinsp;7.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e251.40\u0026thinsp;\u0026plusmn;\u0026thinsp;9.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-6.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.008\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTOF /TOA (N/ mm\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.16\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.18\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-5.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFirst molar OF (N)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14.50\u0026thinsp;\u0026plusmn;\u0026thinsp;2.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e13.57\u0026thinsp;\u0026plusmn;\u0026thinsp;2.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-3.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.035\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eOF ratio of first molar (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e35(22,31.35)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e27(22,30.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.576 (\u003csup\u003ew\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eOF ratio of anterior teeth (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e27.68\u0026thinsp;\u0026plusmn;\u0026thinsp;8.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e36.16\u0026thinsp;\u0026plusmn;\u0026thinsp;6.82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-3.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eOF ratio of premolar(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e44.84\u0026thinsp;\u0026plusmn;\u0026thinsp;9.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e17.86\u0026thinsp;\u0026plusmn;\u0026thinsp;4.21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.853\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eOF ratio of molar (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e27.00(22.50,30.50)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e45(41.00, 51.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.374\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.000\u003csup\u003e**\u003c/sup\u003e (\u003csup\u003ew\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e\u003csup\u003e*\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.05, \u003csup\u003e**\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.01\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e\n \u003ch2\u003e3.4 Correlation of Occlusal Characteristics and zygomatic pillar remodeling\u003c/h2\u003e\n \u003cp\u003eAs shown in the Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e9\u003c/span\u003e, the total occlusal force, total occlusal area, and occlusal force of the first molar all decreased after reduction orthodontic treatment. However, the occlusal force per unit area and the proportion of anterior teeth occlusal force increased, while the proportion of anterior molar occlusal force decreased. Moreover, as illustrated in the Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e14\u003c/span\u003e, the association between the thinning of cortical bone thickness in the middle and upper parts of the zygomatic pillar, reduction of alveolar bone density, and decrease in the cross-sectional area of the pillar becomes more apparent, with the increased occlusal force of the first molar showing a greater trend (r\u0026thinsp;\u0026gt;\u0026thinsp;0.4). Furthermore, the reduction of alveolar bone density (except for △MBbmd1 and △DBbmd2) and the decrease in cross-sectional area were significantly positively correlated (r\u0026thinsp;\u0026gt;\u0026thinsp;0.4) with the decline in the total force and total occlusal area, meaning that the reconstruction of the zygomatic pillar structure significantly affects occlusal force changes.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\n \u003ch2\u003e3.5 Occlusal Stress distribution in T0 and T1\u003c/h2\u003e\n \u003cp\u003eAs shown in Fig. \u003cspan class=\"InternalRef\"\u003e15\u003c/span\u003e, following zygomatic pillar reconstruction, the stress concentration area in the zygomatic alveolar ridge and buccal alveolar bone is reduced, and the stress at the posterior margin of the orbit decreases. However, the stress in the zygomatic arch area behind the temporozygomatic suture and at the intersection of the vertical and horizontal edges of the zygomatic bone significantly increases.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"4 Discussion","content":"\u003cp\u003eIn odontics, it is common knowledge that the maxillary first molar and its associating zygomatic pillar that bears its occlusal force are crucial, and this has led to the development of concepts such as key ridge. Over the years, researchers have extensively discussed the reconstruction of alveolar bone accompanying orthodontic tooth movement, but few have focused on the pillar structures involved in force transmission within the cranium\u003cstrong\u003e.\u003c/strong\u003eTherefore, this study focuses on the remodeling of the zygomatic pillar before and after treatment in patients undergoing orthodontics\u0026nbsp;with premolar extraction\u0026nbsp;, the effect of maxillary first molar movement on zygomatic pillar reconstruction, and further investigates the impact of pillar reconstruction on occlusal features and stress distribution of occlusal forces in the skull.\u003c/p\u003e\n\u003cp\u003ePrimarily, bone remodeling includes two parts: morphological reconstruction and structural reconstruction. Comparing the cross-sectional areas of zygomatic pillars within a constant-height plane, it was found that the cross-sectional area of the lower part of the zygomatic pillar significantly decreased, reflecting a shrinkage in the overall shape of the lower part of the zygomatic pillar.\u0026nbsp;The surface morphology landmarks of the zygomatic pillar's middle section, ZM, and ZP, moved backward, and the ZP point moved medially. This phenomenon\u0026nbsp;maybe associated with the pressure stress on the vertical direction of the zygomaticomaxillary suture and the\u0026nbsp;transversal pressure on zygomatic body when first molar move forward\u003csup\u003e[14]\u003c/sup\u003e. The pressure may have caused bone resorption. At the same time, the EKM point moves mesially, palatally, and extends along with the maxillary first molar. This implies that the starting point of the zygomatic pillar moves with the maxillary first molar, while the middle and upper sections shift backward and medially.\u003c/p\u003e\n\u003cp\u003eThe alveolar bone thickness of the maxillary first molar significantly decreased, which is consistent with previous research with non-extraction patients\u003csup\u003e\u0026nbsp;[11]\u003c/sup\u003e. Moreover, the cortical bone thickness at all height planes, except for the\u0026nbsp;fmt\u0026nbsp;plane, significantly decreased. FEA research might explain this phenomenon\u003csup\u003e[14]\u003c/sup\u003e. As the first molar undergoes orthodontic movement, the pressure stress area also moves forward, causing the anterior cortical bone to be more compressed, and osteoclasts become active, leading to bone resorption. Bone structural reconstruction as seen in the absorption of alveolar bone density is consistent with Chang, H\u0026nbsp;'s\u0026nbsp;study\u003csup\u003e[12]\u0026nbsp;\u003c/sup\u003e. The absence of significant changes in the cortical bone density of the pillar indicates that structural reconstruction is mainly limited to the lower segment of the zygomatic pillar.\u003c/p\u003e\n\u003cp\u003eIt was found that mesial and lingual movements in reduction orthodontic treatment were most closely related to zygomatic pillar remodeling, followed by extusion and tipping. The MLR equation shows that 40% of cortical bone thickness change, coordinate change, and cross-sectional area change are caused by changes of molar movement, suggesting that the movement of the maxillary first molar, especially mesial and palatal movement, is an important cause for zygomatic pillar remodeling in reduction orthodontic treatment patients. Occlusal force decreases after zygomatic pillar remodeling. The overall occlusal force results are consistent with Yoon, W'sview\u003csup\u003e[10]\u003c/sup\u003e, and it was further found that the occusal force of maxillary first molar was lowered, and the force ratio of the anterior teeth increased. This is probably in accordance with the increased stress on the anterior pillar \u003csup\u003e[14]\u003c/sup\u003e. The study further investigated the impact of zygomatic pillar construction on occlusal force, discovering that the more prominent the pillar bone thickness, lower segment bone density, and landmark displacement, the greater the decreasing trend of the maxillary first molar occlusal force. It also affects the total occlusal force and occlusal area, which corresponds to the function of the zygomatic pillar in bearing occlusal forces. After orthodontic treatment\u0026nbsp;with premolar extraction, the overall structure of the zygomatic pillar becomes weaker, leading to a significant decrease in the corresponding occlusal force that can be borne. The occlusal stress analysis of the three-dimensional finite element model after zygomatic pillar remodeling shows a difference compared to the\u0026nbsp;simple\u0026nbsp;tooth alignment model\u0026nbsp;after\u0026nbsp;extraction\u003csup\u003e[8]\u003c/sup\u003e: stress is concentrated in the weak areas of the zygomatic pillar (near the most convex point of the zygomatic arch and the area where the vertical and horizontal edges intersect), implying that the ability of these fracture-prone areas to withstand external force impact is further reduced, lowering the resistance of the zygomatic pillar.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e4.1 \u0026nbsp;Innovantion\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOur study delineated the measurement areas for the zygomatic pillar. Prior research has only qualitatively described the morphology of the zygomatic pillar but has not defined its scope, making it impossible to quantitatively compare the remodeling of the zygomatic pillar. Based on the definition of the zygomatic pillar, this study establishes reference planes for the measurement range by using landmarks on stable bone structures. As it is believed that the outermost boundary of the canine pillar is the IF plane\u003csup\u003e[14\u003c/sup\u003e\u003csup\u003e,\u003c/sup\u003e\u003csup\u003e15]\u003c/sup\u003e., and the zygomatic arch region can serve as a stable area for three-dimensional overlap before and after orthodontics\u003csup\u003e[16]\u003c/sup\u003e, the transverse inner boundary is defined by the IF plane, and the final boundary of the sagittal range is the highest point of the zygomatic-temporal suture. Based on the composition of the pillar, pillar is divided into upper, middle, and lower segments, and the easily remodeled lower and middle sections near the starting point of force are further divided into three and two sections for measurement.\u003c/p\u003e\n\u003cp\u003eThis study subsequently assessed the impact of three-dimensional directional movement of the maxillary first molar on zygomatic pillar remodeling. Prior literature has only associated individual tooth movement indices with alveolar bone thickness and density remodeling\u003csup\u003e[2,11]\u003c/sup\u003e, Moreover, this study explained the degree of impact of different maxillary first molar movement modes on zygomatic pillar remodeling through linear regression equations, laying the groundwork for predicting zygomatic pillar remodeling. At the same time, this study, for the first time, constructed two three-dimensional finite element models of a patient's zygomatic pillar before and after orthodontic treatment with premolar extraction. The average occlusal force of the same group of patients before and after treatment was applied, respectively. These models simulate the occlusal force stress distribution before and after the remodeling of the zygomatic pillar to the greatest extent possible, further explaining the impact of zygomatic pillar remodeling on occlusal characteristics and stress distribution.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e4.2 \u0026nbsp;Clinical significance\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e4.2.1 \u0026nbsp;Anchorage\u003c/strong\u003e : How to control anchorage is an issue repeatedly explored by orthodontists. Particularly during reduction orthodontic treatment, the retraction of anterior teeth will inevitably generate counteracting forces of equal magnitude and opposite direction. When not using bone screws or other TAD devices, these reaction forces mainly affect the posterior teeth, and exceeding a certain threshold will cause the posterior teeth to move forward. When there is significant crowding and the space for anterior teeth retraction is large, we do not want the forward movement of the posterior teeth to consume the space. At the same time, this study also proved that the mesial movement of the molars is strongly related to the remodeling of the zygomatic pillar, which becomes another condition restricting the movement of the maxillary first molar. Based on this study, in our clinical practice, we should consider not only the allocation of space but also adopt methods such as \"posterior teeth ligation,\" \"two-step method,\" \"posterior bending,\" and use transpalatal arch, TPA, etc., to control excessive mesial movement of the maxillary first molar to prevent significant decline in occlusal function due to zygomatic pillar remodeling.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e4.2.2 \u0026nbsp;Implant screw\u003c/strong\u003e: The zygomatic alveolar ridge of the zygomatic pillar is a common implantation site for temporary maxillary anchorage devices due to its dense bone quality and relatively wide cortical bone thickness. Scholars found that the thickest area tends to be between second premolar andfirst molar, and it is generally the primary site to consider for implantation. The common implantation timing for anchorage screws is after the teeth are aligned and leveled, with their axes properly positioned. However, our research found that as the first molar moves forward, the bone cortex of the zygomatic pillar(including zygomatic crest ), which is a common implantation site for anchorage screws, becomes thinner. During the alignment and leveling process, the maxillary first molar may have moved forward, which could affect the effectiveness of the anchorage screw implantation. Consequently, by adding devices such as transpalatal arches, the forward movement of the maxillary first molar during the alignment and leveling phase can be inhibited, along with reducing the decrease in cortical bone thickness. Alternatively, changing the implantation site, such as placing it between teeth 6 and 7 or using palatal mini-implants, can help avoid this potential risk. Moreover, if the molar is still required to move forward during the gap closure process after the insertion of mini-implants, it may affect the stability of the implanted mini-implants, becoming a partial cause of their dislodgment.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e4.2.3 \u0026nbsp;Facial aesthetics:\u003c/strong\u003e The remodeling findings of this study may also have implications for facial aesthetics, as it was found that as the first molar moves mesially and lingually, the zygomatic point moves inward and backward, and the zygomatic-sphenoid suture point moves backward. These negative changes in bony prominences may partly explain the negative changes in the soft tissues of the cheekbone and nasolabial groove observed in some patients after orthodontic treatment\u003csup\u003e[18-19]\u003c/sup\u003e, such as the phenomenon of \"brace face\" in Chinese female orthodontic patients. It is speculated that these facial changes may not be solely attributed to soft tissue remodeling but also involve bony prominences remodeling. Restricting the movement of the first molar may also offer the possibility to reduce the effect of \"brace face.\"\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e4.2.4 \u0026nbsp;Stabilization:\u003c/strong\u003e Lastly, the weakened zygomatic pillar after remodeling, by affecting the magnitude and distribution of occlusal forces, may also have an impact on the stability of orthodontic treatment outcomes since\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e4.3 \u0026nbsp;Limitation\u003c/strong\u003es\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;The shortcomings of this study lie in the fact that it does not yet include research on the remodeling of the entire alveolar process at different stages of retention after orthodontic treatment completion. The stability of the zygomatic pillar during the retention period is also crucial for the long-term effectiveness of the orthodontic treatment since it was suggested that occlusal force may recover during the retention period. Therefore, there is a need to further expand the sample size and extend the follow-up observation time.\u003c/p\u003e"},{"header":"5 Conclusions","content":"\u003cp\u003eDuring orthodontic treatment with premolar extraction, the 3D movement and angular changes of the maxillary first molar resulted in increased fragility of the zygomatic pillar structure and morphology. This remodeling contributed to reduced occusal force, with concentration in the weak areas of zygomatic pillar.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e: The first draft of the manuscript was written by Size Li who is the first author of this article and completed the data acquisition, analysis of data, picture drawing and drafting the manuscript. The 3D finite element modeling and analysis were mainly completed by Han Bao. Data collection was jointly contributed to by Xiaojie Su,\u0026nbsp;Liping Xiong, Qianwen Yin, and Deao Gu. Substantial assistance in the revision and editing of the manuscript\u0026nbsp;was rendered by Leiying Miao. Conception and design of the study were proposed by Chao Liu .All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e : The study was partially supported by Key Project supported by Medical Science and Technology Development Foundation, Nanjing Department of Health under Grant, ZKX22055 and \"2015\"Cultivation Program for Reserve Talent s for Academic Leaders of Nanjing Stomatological School,Medical School of Nanjing Univeristy, 0223A210.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e:\u0026nbsp;All data supporting the fndings of this study are available within the paper.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e:\u0026nbsp;This study was approved by the Ethics Committee of the Affiliated Stomatology Hospital of Medical School,Nanjing University (Approval No. JX-2022-NL05).\u0026nbsp;Written informed consent was obtained from all individual participants included in the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e: Informed permission for publication was acquired from all patients.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;interests\u003c/strong\u003e: The authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eWilliam R, Henry W, Brent E, et al. Contemporary Othodontics[M].China: Elisevier 2019.248\u003c/li\u003e\n\u003cli\u003eEksriwong, T., \u0026amp; Thongudomporn, U. (2021). Alveolar bone response to maxillary incisor retraction using stable skeletal structures as a reference. The Angle orthodontist, 91(1), 30\u0026ndash;35. https://doi.org/10.2319/022920-146.1\u003c/li\u003e\n\u003cli\u003eSicher H, Du Brul EL(1970) Oral Anatomy. 5th ed. CV Mosby ,St. Louis\u003c/li\u003e\n\u003cli\u003eSa Sana, S., Kondody, R. T., Talapaneni, A. K., Fatima, A., \u0026amp; Bangi, S. L. (2021). Occlusal stress distribution in the human skull with permanent maxillary first molar extraction: A 3-dimensional finite element study. American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics, 160(4), 552\u0026ndash;559. https://doi.org/10.1016/j.ajodo.2020.05.022\u003c/li\u003e\n\u003cli\u003eGross, M., Gracis, S., Gamborena, I., Meyenberg, K., Shifman, A., \u0026amp; Nissan, J. (2015). The science and art of occlusion and oral rehabilitation ,Quintessence publishing \u003c/li\u003e\n\u003cli\u003eHilloowala, R., \u0026amp; Kanth, H. (2007). The transmission of masticatory forces and nasal septum: structural comparison of the human skull and Gothic cathedral. Cranio:the journal of craniomandibular practice, 25(3), 166\u0026ndash;171. https://doi.org/10.1179/crn.2007.026\u003c/li\u003e\n\u003cli\u003eCreekmore T. D. (1997). Where teeth should be positioned in the face and jaws and how to get them there. Journal of clinical orthodontics : JCO, 31(9), 586\u0026ndash;608\u003c/li\u003e\n\u003cli\u003eChoi, D. S., Cha, B. K., Jang, I., Kang, K. H., \u0026amp; Kim, S. C. (2013). Three-dimensional finite element analysis of occlusal stress distribution in the human skull with premolar extraction. The Angle orthodontist, 83(2), 204\u0026ndash;211. https://doi.org/10.2319/020112-89.1\u003c/li\u003e\n\u003cli\u003eFrost H. M. (1994). Wolff\u0026apos;s Law and bone\u0026apos;s structural adaptations to mechanical usage: an overview for clinicians. The Angle orthodontist, 64(3), 175\u0026ndash;188. https://doi.org/10.1043/0003-3219(1994)064\u0026lt;0175:WLABSA\u0026gt;2.0.CO;2 \u003c/li\u003e\n\u003cli\u003eYoon, W., Hwang, S., Chung, C., \u0026amp; Kim, K. H. (2017). Changes in occlusal function after extraction of premolars: 2-year follow-up. The Angle orthodontist, 87(5), 703\u0026ndash;708. https://doi.org/10.2319/112116-836.1 \u003c/li\u003e\n\u003cli\u003eMorais, J. F., Melsen, B., de Freitas, K. M. S., Castello Branco, N., Garib, D. G., \u0026amp; Cattaneo, P. M. (2018). Evaluation of maxillary buccal alveolar bone before and after orthodontic alignment without extractions: A cone beam computed tomographic study. The Angle orthodontist, 88(6), 748\u0026ndash;756. https://doi.org/10.2319/101117-686.1 \u003c/li\u003e\n\u003cli\u003eChang, H. W., Huang, H. L., Yu, J. H., Hsu, J. T., Li, Y. F., \u0026amp; Wu, Y. F. (2012). Effects of orthodontic tooth movement on alveolar bone density. Clinical oral investigations, 16(3), 679\u0026ndash;688. https://doi.org/10.1007/s00784-011-0552-9\u003c/li\u003e\n\u003cli\u003eDai, F. F., Xu, T. M., \u0026amp; Shu, G. (2019). Comparison of achieved and predicted tooth movement of maxillary first molars and central incisors: First premolar extraction treatment with Invisalign. The Angle orthodontist, 89(5), 679\u0026ndash;687. https://doi.org/10.2319/090418-646.1 \u003c/li\u003e\n\u003cli\u003eCattaneo, P. M., Dalstra, M., \u0026amp; Melsen, B. (2003). The transfer of occlusal forces through the maxillary molars: a finite element study. American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics, 123(4), 367\u0026ndash;373. https://doi.org/10.1067/mod.2003.73 \u003c/li\u003e\n\u003cli\u003eLinnau, K. F., Stanley, R. B., Jr, Hallam, D. K., Gross, J. A., \u0026amp; Mann, F. A. (2003). Imaging of high-energy midfacial trauma: what the surgeon needs to know. European journal of radiology, 48(1), 17\u0026ndash;32. https://doi.org/10.1016/s0720-048x(03)00205-5 \u003c/li\u003e\n\u003cli\u003ePrado, F. B., Freire, A. R., Cl\u0026aacute;udia Rossi, A., Ledogar, J. A., Smith, A. L., Dechow, P. C., Strait, D. S., Voigt, T., \u0026amp; Ross, C. F. (2016). Review of In Vivo Bone Strain Studies and Finite Element Models of the Zygomatic Complex in Humans and Nonhuman Primates: Implications for Clinical Research and Practice. Anatomical record (Hoboken, N.J. : 2007), 299(12), 1753\u0026ndash;1778. https://doi.org/10.1002/ar.23486 \u003c/li\u003e\n\u003cli\u003eNada, R. M., Maal, T. J., Breuning, K. H., Berg\u0026eacute;, S. J., Mostafa, Y. A., \u0026amp; Kuijpers-Jagtman, A. M. (2011). Accuracy and reproducibility of voxel based superimposition of cone beam computed tomography models on the anterior cranial base and the zygomatic arches. PloS one, 6(2), e16520. https://doi.org/10.1371/journal.pone.0016520 \u003c/li\u003e\n\u003cli\u003eZhou, Q., Gao, J., Guo, D., Zhang, H., Zhang, X., Qin, W., \u0026amp; Jin, Z. (2023). Three dimensional quantitative study of soft tissue changes in nasolabial folds after orthodontic treatment in female adults. BMC oral health, 23(1), 31. https://doi.org/10.1186/s12903-023-02733-5\u003c/li\u003e\n\u003cli\u003eGao, J., Wang, X., Qin, Z., Zhang, H., Guo, D., Xu, Y., \u0026amp; Jin, Z. (2022). Profiles of facial soft tissue changes during and after orthodontic treatment in female adults. BMC oral health, 22(1), 257. https://doi.org/10.1186/s12903-022-02280-5\u003c/li\u003e\n\u003cli\u003eLee, S. H., Fang, M. L., Choi, Y. J., Yu, H. S., Kim, J. H., Hu, K. S., \u0026amp; Lee, K. J. (2023). Changes in masticatory performance during the retention period following 4-premolar extraction and non-extraction orthodontic treatment. Clinical oral investigations, 27(6), 2609\u0026ndash;2619. https://doi.org/10.1007/s00784-022-04817-y\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"clinical-oral-investigations","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"cloi","sideBox":"Learn more about [Clinical Oral Investigations](http://link.springer.com/journal/784)","snPcode":"784","submissionUrl":"https://submission.nature.com/new-submission/784/3","title":"Clinical Oral Investigations","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Orthodontic treatment, Zygomatic pillar, Bone remodeing, the Maxillary Molar Movement , the Maximum occlusal force and occlusal contact area, Finite element analysis ","lastPublishedDoi":"10.21203/rs.3.rs-3824244/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3824244/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjective\u003c/strong\u003e: To evaluate zygomatic pillar changes during orthodontic treatment with premolar extraction, then analyze the effects of maxillary first molar movement on zygomatic pillar remodeling, and examine occlusal characteristics and stress distribution after reconstruction.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e: 25 premolar extraction patients were included. Zygomatic pillar measurement range was defined, and cross-sectional areas, surface landmark coordinates, and alveolar and cortical bone thickness and density changes were assessed using Mimics based on the CBCT taken before(T0)and after treatment(T1). Multiple linear regression was employed to explain correlations between zygomatic pillar changes and maxillary first molar 3D movement and rotation. Correlations between pillar remodeling and occlusal characteristics, as analyzed by Tteester, were calculated. Pre- and post-reconstruction 3D finite element models (FEA) were constructed and loaded with average occlusal force of two period , respectively.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e: Zygomatic pillar cross-sectional area, landmark coordinates, bone thickness and alveolar bone density decreased. The mesial and lingual movement of the maxillary molars was strongly correlated with these changes, accounting for \u0026gt;40% variations. Occusal stress concentrated on weak areas after remodeling.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions\u003c/strong\u003e: Orthodontic treatment with premolar extraction led to zygomatic pillar remodeling, making it more fragile and reducing the occusal force of the maxillary first molar and the entire dentition with stress concentrating on weak areas.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical Relevance\u003c/strong\u003e: No other study has focused on the effects of orthodontics on pillar structures.This research indicates that mesial movement of the maxillary first molar weakened zygomatic pillar, reduced occlusal function, and providing insights for insrting anchorage screws and facial aesthetics.\u003c/p\u003e","manuscriptTitle":"Orthodontic Maxillary Molar Movement-Induced Zygomatic Pillar Remodeling and its Consequences on Occlusal Characteristics and Stress Distribution","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-01-12 17:33:22","doi":"10.21203/rs.3.rs-3824244/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-03-18T13:57:25+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-03-12T17:01:33+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"20bc698e-2f00-441f-8a69-a6345ea89a93","date":"2024-02-02T15:52:26+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-01-25T16:33:01+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"0b902131-07e3-48f1-80c9-1a4ee7c35255","date":"2024-01-19T11:11:53+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-01-19T11:10:03+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-01-11T01:01:37+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-01-11T01:01:37+00:00","index":"","fulltext":""},{"type":"submitted","content":"Clinical Oral Investigations","date":"2023-12-30T14:42:23+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"clinical-oral-investigations","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"cloi","sideBox":"Learn more about [Clinical Oral Investigations](http://link.springer.com/journal/784)","snPcode":"784","submissionUrl":"https://submission.nature.com/new-submission/784/3","title":"Clinical Oral Investigations","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"02937647-ca90-4206-b5e6-49c15974705e","owner":[],"postedDate":"January 12th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-06-21T15:18:38+00:00","versionOfRecord":{"articleIdentity":"rs-3824244","link":"https://doi.org/10.1007/s00784-024-05713-3","journal":{"identity":"clinical-oral-investigations","isVorOnly":false,"title":"Clinical Oral Investigations"},"publishedOn":"2024-06-15 15:18:38","publishedOnDateReadable":"June 15th, 2024"},"versionCreatedAt":"2024-01-12 17:33:22","video":"","vorDoi":"10.1007/s00784-024-05713-3","vorDoiUrl":"https://doi.org/10.1007/s00784-024-05713-3","workflowStages":[]},"version":"v1","identity":"rs-3824244","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3824244","identity":"rs-3824244","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}