The preliminary study of the effects of individual musculoskeletally stable position in the treatment of temporomandibular disorders

The preliminary study of the effects of individual musculoskeletally stable position in the treatment of temporomandibular disorders | 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 The preliminary study of the effects of individual musculoskeletally stable position in the treatment of temporomandibular disorders Zhi Zhang, Xiao Luo, Xiaoqing Li, Bing Shi, Lijun Tan This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4582957/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 13 Sep, 2024 Read the published version in BMC Oral Health → Version 1 posted 12 You are reading this latest preprint version Abstract Objective : TMD (Temporomandibular Joint Disorders) is the dysfunction of group of muscles and bones in the joint area, the main symptom of TMD is the pain of the chewing muscles and (or) the temporomandibular joints, which seriously affects the life qualities of patients and even social behaviors. Stabilization splint is one of the commonly used effective reversible treatment, the determination of the jaw position is the critical point in the process of treatment. Methods: In this study, we firstly used Fricton Index to evaluate the clinical curative effect of TMD with the treatment of IMS (Individual MusculoskeletallyStable) position stabilization splint; then CBCT (Cone Beam Computerized Tomography) was used to observe the TMJ condylar position changes of TMD before and after the treatment of IMS stabilization splint; finally sEMG (surface-Electromyogram) was used to observe the changes of electromyography of AT (anterior temporalis) and MM (masseter muscle) of TMD before and after the treatment of IMS stabilization splint. Results and conclusions: IMS stabilization splint is one of efficient reversible treatments for TMD, which can relieve and even eliminate the TMD symptoms, especially for ease of pain and corrective to jaw movement disorder; After the treatment of IMS, posterior space of TMJ has the tendency of increasing; IMS stabilization splint may ease even cure the TMD by removing the masticatory muscle disorders, terminating the masticatory muscles antagonism between bad function so as to make them function in harmony with each other. Temporomandibular Joint Disorders Stabilization Splint Surface Electromyogram Individual Musculoskeletally Stable Position Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 1 Background TMD (Temporomandibular Joint Disorders) is a common oral-maxillofacial disease [1]. Epidemiology shows that, approximately 75% of the world’s population has one sign and at least 33% has one symptom of TMDs [2]. TMDs are dysfunctions of muscle groups and bones in TMJ (Temporomandibular Joint) areas, main symptoms of TMDs are pains in masticatory muscles around TMJs and (or) inside TMJs themselves, which in turn seriously affect the patients’ life qualities and social behaviors. According to the classification of risk factors by de Boever [3], occlusal patterns, neuromuscular system disorders, social and emotional statuses, etc, tend to be predominant in TMD occurrences. Unfortunately, a direct correlation between psychophysiological or psychological accounts and TMD is not found yet [4], thus reliable and effective treatments to TMD are not available currently. As to the treatment principle of TMD, reversible comprehensive conservative treatment was taken at first, such as splint therapy and psychotherapy; the final choice is irreversible treatment, including selected grinding, fixed prosthesis treatment, orthognathic surgery and orthodontic treatment. Clinicians will not start orthodontic treatments until the patients’ TMJs are in a better condition, condyles have been repositioned following the changes of relationships between mandibles and maxillae with the method of RW (Roth Williams) philosophy [5, 6]. The most orthopedically stable joint position which exists when the condyles in the most superoanterior positions of the articular fossae, resting against the posterior articular slopes with discs properly interposed. The condyle position when the elevator muscles activated with no occlusal influences is therefore considered to be the most MSP (musculoskeletally stable position) of the mandible [7] and is also the theoretical foundation of RW philosophy. If the condyles are repositioned in MSP by splints, the maximum intercuspal position is formed, healthy TMJ, coordinated occlusion and facial aesthetics could be obtained via this approach in order to achieve long-term stability of orthodontics. However, there may are still a few flaws in RW philosophy: (i) For clinicians, it is difficult to get condyles in the most superoanterior position, so the repeatability cannot be guaranteed; (ii) The most superoanterior position may not be the suitable position since TMJ, muscles, ligaments, facial connections, as well as neural and circulatory innervations are all intimately related[8]. (iii) Acute pain may be caused by huge positional changes between the articular discs and the condyles, bad emotional status is still a significant risk factor leading to TMD [9]. Stomatognathic system, an integral component of the upper body, is basically composed of the head, neck and shoulder girdle. Clinicians should not treat every patient with the same approach, thus IMS (Individual Musculoskeletally Stable) position was innovatively proposed which is different from Dawson’s manual reposition [10]. IMS position may not be the most superoanterior position, however, it may be the position where TMJ, muscles, ligaments, facial connections and nerve functions are in harmony corresponding to the individual anatomy. The aim of this research is to conduct a preliminary understanding of the IMS splint therapeutic effect by evaluation means of Fricton Index [11], CBCT (Cone-beam Computerized Tomography) and sEMG (surface Electromyogram). Specifically, we seek to bring into focus the result on the mandibular condyle position in order to break a new path to treat TMD, with both clinical effect and the balance of the stomatognathic system taken into consideration. 2 Methods Participants A group of 31 consecutive patients with TMD (joint structure disorder and masticatory muscle disorders) were identified as members for the study inclusion. All patients received examination and treatment for TMDs at the Department of TMJ, West China Hospital of Stomatology, Sichuan University from 2019 to 2022. The research was approved by the Medical Ethics Committee of West China Hospital of Stomatology, Sichuan University (No. WCHSIRB-D-2016-073). The initial TMD diagnosis was based on cone beam computed tomography (CBCT) in combination with clinical findings obtained from our standardized TMJ clinical examinations at the Department of TMJ. Radiological pathological finding was defined as conditions deviating from the normal TMJ space on two-dimensional CBCT cuts. What’s more, the initial TMD diagnosis was made based on clinical examinations, orofacial symptoms were of great importance, and Fricton Index was used in this study for assessment. Inclusion and exclusion criteria The inclusion criteria were: (i) TMD diagnosis according to the criteria of American Dental Association[7]; (ii) no inflammation in the mandibular condyle according to the examination of CBCT; (iii) patients were capable of understanding our treatment and willing to co-operate with us. The exclusion criteria were: (i) patients had been treated with occlusal reconstruction in the way of orthodontics and/or prosthetics; (ii) there was inflammation in the mandibular condyle according to the examination of CBCT; (iii) the score of Symptom Checklist 90 (SCL-90) [12] was more than 160; (iv) patients with TMJ trauma or other systemic disease; (v) patients failed to accept orthognathic surgery which was considered possible. The usage of Stabilization splint Patients were asked to bite the cotton roll for at least 20 minutes in order to smash the procedure of masticatory muscles, and then they closed their mouth as freely as they can in order to find a comfortable position, both in muscles and bones, during which the bite recording was made. The stabilization splint used in our study was fabricated from impression of upper dental arch and a silicone rubber bite recording of the IMS position. The splint was fabricated as a “flat” splint with no impression for occluding guidance in the posterior teeth, however, there should be incisors guidance in protrusive movement and canine guidance in lateral movement according to the functional occlusion (Fig. 1 ). Patients were instructed to wear the splint all day long except when they were brushing their teeth or having more serious clinical symptoms. The splint was ground individually, based on functional occlusion, weekly in the first month, then monthly in the next months until stable. Additionally, participants were comforted in each visit. Clinical curative effect At pre and post-treatment, all patients completed a standardized questionnaire in combination with clinical examinations by one rater. Fricton Index [11, 13] was implied in this study, which was comprised of Dysfunction Index (DI) and Palpation Index (PI), the Craniomandibular Index (CMI) was developed to provide a standardized measure of problems severity in the mandibular movement, TMJ noise, muscle and joint tenderness for use in epidemiological and clinical outcome studies. TMJ Space Distance At pre and post-treatment, all patients had a radiological examination based on CBCT, Joint-space distances between the condyle and glenoid fossa were divided into anterior, upper and posterior spaces in the sagittal plane according to Kamelchuk [14] and the inner and outer spaces in the coronal plane according to Ikeda [15]. Specific details (Fig. 2 ). Surface Electromyogram At pre and post-treatment, all patients were tested in the Chewing Function Room, West China Hospital of Stomatology, Sichuan University where it was silent enough and the temperature was between 22–25℃. Electromyographic devices were applied to the patients in this study (K-7 EMG, Myotronics Noromed, Inc. Kent, WA), and each patient was asked to sit comfortably in an upright chair with eyes slightly closed. The EMG device was used to measure each patient’s two paired muscles (anterior temporalis and masseter muscles). Measurements were performed after each patient was asked to assume a resting mandibular position (mandibular posture position, MPP) where the teeth were not touching. Three successive sets of data were obtained and we took the average of them. Then maximum voluntary clench (MVC) position was performed in order to measure the EMG of the muscles with the device by asking each patient to alternately clench his/her teeth maximally three times for two seconds with two seconds of relaxation between each clench period, which was repeated for three times and we took the average of them (Fig. 3 and Fig. 4 ). Statistics Pre and post-treatment outcome variables were compared to themselves by paired Student’s t-tests after the data were tested for normal distribution, and p < 0.05 was considered significant. 3 Results Among the 31 patients (ranging from 18 through 26 years old, including 7 males and 24 females), 17 were in the group of joint structure disorders, 14 were in the group of masticatory muscle disorders (The treatment time ranged from 6 through 8 months). Clinical curative effect The mandibular movement score was 2.45, the joint palpation score was 0.35, the dysfunction index was 0.14, the craniomandibular index score was 0.10 and there was statistical difference ( p 0.05) (Table 1 and Fig. 5 ). Table 1 Comparisons of Fricton Index in patients with TMD before and after treatment (n = 31) ±s Scales Pre-treatment Post-treatment Difference value t p Mandibular Movement (MM) 5.45 ± 2.50 2.45 ± 1.06 -3.00 ± 2.54 -6.568 0.000 Joint Noise (JN) 1.42 ± 1.12 1.03 ± 0.84 -0.39 ± 1.23 -1.753 0.090 Joint Palpation (JP) 1.03 ± 0.84 0.35 ± 0.48 -0.67 ± 0.98 -3.851 0.001 Dysfunction Index (DI) 0.30 ± 0.11 0.14 ± 0.05 -0.16 ± 0.11 -7.749 0.000 Palpation Index (PI) 0.13 ± 0.06 0.06 ± 0.04 -0.07 ± 0.06 -7.228 0.000 Craniomandibular Index (CMI) 0.21 ± 0.07 0.10 ± 0.03 -0.12 ± 0.07 -9.218 0.000 TMJ Space Distance The anterior space of the left temporomandibular joint became smaller (the difference is -0.61 ± 0.91 mm), and the difference was statistically significant ( p < 0.05); the posterior, upper, inner and outer space became bigger, and the change of the posterior space was the most obvious (0.28 ± 1.42 mm) while the change of the outer space was the smallest (0.04 ± 1.38 mm), however, none of them was statistically different ( p > 0.05) (Table 2 and Fig. 6 ). The anterior space of the right temporomandibular joint became smaller (the difference is -0.12 ± 0.90 mm) which had no statistical significant difference ( p > 0.05); the posterior, upper, inner and outer space all became bigger, and the change of the inner space was the most obvious (0.32 ± 0.81 mm) which had significant statistical difference ( p 0.05). The posterior and the upper space had smaller changes (0.11 ± 0.70 mm and 0.05 ± 1.01 mm respectively) (Table 2 and Fig. 6 ). The anterior spaces of both sides of the TMJs became smaller (the difference is -0.36 ± 0.93 mm), which had significant statistical differences ( p < 0.05); the posterior, upper, inner and outer space all became bigger, and the change of the inner space was the most obvious (0.26 ± 0.80 mm) which had the significant statistical difference ( p 0.05), the outer space had the smallest change (0.08 ± 1.14 mm) (Table 3 and Fig. 6 ). Table 2 Comparisons of the left and the right temporomandibular joint spaces before and after treatment (n = 31) ±s, mm Space Pre-treatment Post-treatment Difference value t p Left Anterior space 2.70 ± 0.79 2.09 ± 0.61 -0.61 ± 0.91 -3.72 0.001 Posterior space 2.66 ± 1.24 2.95 ± 1.18 0.28 ± 1.42 1.12 0.274 Upper space 2.56 ± 0.98 2.78 ± 1.06 0.22 ± 1.03 1.20 0.240 Inner space 2.32 ± 0.61 2.52 ± 0.69 0.20 ± 0.80 1.37 0.181 Outer space 2.57 ± 1.06 2.61 ± 1.11 0.04 ± 1.38 0.16 0.877 Right Anterior space 2.71 ± 0.66 2.60 ± 0.76 -0.12 ± 0.90 -0.74 0.466 Posterior space 2.02 ± 0.64 2.13 ± 0.38 0.11 ± 0.70 0.89 0.383 Upper space 2.61 ± 1.04 2.66 ± 0.42 0.05 ± 1.01 0.28 0.780 Inner space 2.47 ± 0.91 2.79 ± 0.64 0.32 ± 0.81 2.16 0.039 Outer space 2.39 ± 0.62 2.52 ± 0.70 0.13 ± 0.87 0.83 0.412 Table 3 Comparisons of bilateral temporomandibular joint spaces before and after treatment (n = 62) ±s, mm Space Pre-treatment Post-treatment Difference value t p Anterior space 2.71 ± 0.73 2.34 ± 0.73 -0.36 ± 0.93 -3.07 0.003 Posterior space 2.34 ± 1.03 2.54 ± 0.96 0.20 ± 1.11 1.40 0.167 Upper space 2.58 ± 1.00 2.71 ± 0.80 0.14 ± 1.02 1.06 0.294 Inner space 2.40 ± 0.77 2.65 ± 0.68 0.26 ± 0.80 2.51 0.015 Outer space 2.48 ± 0.86 2.57 ± 0.92 0.08 ± 1.14 0.58 0.564 Surface Electromyogram When the TMJs were in the mandibular postural position, the electromyogram of bilateral anterior temporalis decreased, wherein the right side decreased by 0.587 ± 1.758 µV which had no statistical difference ( p > 0.05), and the left side decreased by 0.594 ± 0.935 µV which had statistical difference ( p 0.05) (Table 4 and Fig. 7 ). During the maximum voluntary clench, the electromyogram of the left and right anterior temporalis decreased by 3.129 ± 29.212 µV and 6.323 ± 39.219 µV respectively which had no statistical difference ( p > 0.05); the electromyogram of the left and right masseter muscles increased by 1.613 ± 47.623 µV and 2.290 ± 63.522 µV respectively which had no statistical difference ( p > 0.05) (Table 5 and Fig. 7 ). Table 4 Comparisons of EMG during MPP before and after treatment (n = 31) ±s, µV Muscles Pre-treatment Post-treatment Difference value t p Left Anterior Temporalis 2.023 ± 1.008 1.429 ± 0.440 -0.594 ± 0.935 -3.534 0.001 Right Anterior Temporalis 2.752 ± 1.872 2.165 ± 0.668 -0.587 ± 1.758 -1.859 0.073 Left Masseter Muscle 0.797 ± 0.266 0.816 ± 0.173 0.019 ± 0.323 0.334 0.741 Right Masseter Muscle 0.984 ± 0.415 1.045 ± 0.234 0.061 ± 0.451 0.756 0.456 Table 5 Comparisons of EMG during MVC before and after treatment (n = 31) ±s, µV Muscles Pre-treatment Post-treatment Difference value t p Left Anterior Temporalis 66.290 ± 27.452 63.161 ± 20.648 -3.129 ± 29.212 -0.696 0.555 Right Anterior Temporalis 76.774 ± 36.179 70.452 ± 25.878 -6.323 ± 39.219 -0.898 0.377 Left Masseter Muscle 83.097 ± 46.180 84.710 ± 32.964 1.613 ± 47.623 0.189 0.852 Right Masseter Muscle 82.968 ± 63.312 85.258 ± 52.686 2.290 ± 63.522 0.201 0.842 4 Discussion Clinical curative effect Pain, joint noise and limited movement are the common symptoms of TMD, and clinical evaluation of its therapeutic effect is always limited to qualitative description stage, such as obvious effect, effective or ineffective, however, descriptive and subjective reports should be avoided to evaluate the degree of TMD dysfunction or evaluate the TMD therapeutic effect. Fricton disorder index was objective and reliable to a certain extent, which could be used in clinical practice to conduct quantitative and objective evaluation of TMD treatment effect [11, 13, 16]. In our research, immediate pain reliefs of 21 patients with TMDs were reported. The splint used in the research was mainly stabilization splint covering the entire dentition of the patient's upper jaw which simulated Roth functional occlusion concept. The stabilization splint had a good application prospect in the treatment of maxillofacial pain by other researches [17, 18]. In this research, 24 patients with TMDs had joint noises before treatment. After 6–8 months of splint treatment, the joint noises of only 7 patients had disappeared significantly, of which 9 had relieved and 8 had no change. Joint noise mainly indicates bounce, friction and cracking, etc. Bounce was chosen for the research, and there are two pathogenesis, one occurs at the beginning of the opening, which is the anterior disc displacement with reduction, and the other often occurs at the end of the opening with hyper function of pterygoid. In the research, the mandibular movement state of 31 TMD patients had been significantly improved, and the reason may be the separation of upper and lower jaw, the bad muscle memory type of the past was eliminated, then the bad guidance of the musculoskeletal state gradually was eliminated, the open mouth type gradually recovered to be consistent. Moreover, due to the increases of the height between jaws, the negative pressure in the joint cavity was reduced and the adhesive tissue was loosened, thus the mouth opening degree improved. Leite [19] also suggested that the ease of pain of TA maybe a possible potential use of TMDs for mouth opening, our study also found the decrease of sEMG of TA in MPP. TMJ Space Distance CBCT can reflect the bone changes of temporomandibular joint from three-dimensional direction, and the changes of joint space can be observed easier [20]. It was generally believed that condylar displacement may be one of the important imaging manifestations of TMD [21]. Major [22] found that the change of joint space might be associated with the displacement of articular disc to some extent, and the detection of condyle position by CBCT might be used to predict the location of articular discs. Zhang [23] had found that there was no significant statistical difference between the joint spaces measured by CBCT and those measured by actual impression (P = 0.305). It can be considered that CBCT has certain reliability and authenticity in measuring temporomandibular joint spaces. The joint space is of great significance in the diagnosis and treatment of TMD, the previous studies showed that the proportion of small posterior space of patients with TMDs was significantly higher than that of asymptomatic controls [24], the possible reason is that smaller posterior spaces may produce more pressure to the double plate areas, which is loose connective tissues that is rich in blood vessels and nerves. On the contrary, when the condyle process moves forward, the vein will be filled to provide nutrition for the joint area [25] [26]. When long-term compression causes dysfunction in the bilateral plate area, signs and symptoms related to TMD may appear. Ikeda [15] had used Kamelchuk method [14] to measure joint spaces in 24 TMJs of 22 healthy people without joint symptoms, and the anterior, posterior and superior joint spaces were 1.3 ± 0.2mm, 2.1 ± 0.3mm and 2.5 ± 0.5mm, respectively. In this research, joint spaces were measured in 31 TMD patients before treatment, and the anterior, posterior, and upper joint spaces were 2.71 ± 0.73 mm, 2.34 ± 1.03 mm and 2.58 ± 1.00 mm respectively. The anterior spaces of TMD patients increased significantly while the mean value of the posterior spaces decreased but the difference was not significant, and it may be related to the morphological changes of condyles in TMD patients. Patients in this research might be subject to occlusion interference or early contact. In order to avoid the nerve-muscle damage, the adaptive change was produced, perhaps the reconstruction of condyle. However, symptoms related with TMDs might appear when the change went beyond TMJ physiological tolerance [6]. The RW-splint treatment showed a certain deviation between the final trend of condyle movement and the position of manipulative reduction of occlusal reconstruction before treatment, which was worth further study. In this research, 31 TMD patients after the treatment of IMS stabilization splint were carried on the statistical analysis in the joint spaces on both sides. It showed that there was a tendency to decrease in the anterior joint space, however, posterior, upper, inner and outer joint space had the trend of increase, the inner space was the most significant. There were different changes on the left and right side of the condylar joint spaces, and the standard deviation was obvious, which indicated that the condylar position had a very high individuation due to the neuromuscular, anatomical physiological and psychological factors. In the term of one individual, bilateral asymmetry of neuromuscular function, asymmetry of condyle morphologies and rotation of condyles would result in the asymmetry of bilateral motion. Although the variation of the bilateral joint spaces is different due to the individual characteristics, the general trend is the reduction of the anterior joint space. Surface Electromyogram Electromyography was the most reliable and objective technique to evaluate muscle functions and efficacy by monitoring muscle potentials in clinical practices [27], which could evaluate the degree and duration of muscle activities. One method is the sEMG (surface electromyography), this non-invasive and painless electrophysiological activity recording the method of muscle requires the electrode as an auxiliary tool, and the non-invasive properties became its most important advantage [28]. The main goal of sEMG is to monitor the electrophysiological signals of muscle fibers in the attached area through the surface electrodes, these signals are the sum of the activities of multiple motor units in this area. Visser [29] conducted statistical analysis on the EMG monitoring values of masseter muscle and temporal muscle in healthy people within 2 days, and the correlation values showed no significant difference or asymmetry. Accurate quantitative analysis of muscle electrophysiological activities by sEMG simplified the quantitative analysis in the oral and maxillary system and provided the possibility of objective evaluations of muscle functions [28]. In this research, the EMGs of bilateral anterior temporalis and masseter muscles were 2.023 µV, 2.752 µV, 0.797 µV, 0.984 µV respectively when patients are in the mandibular postural position before the treatment. Scopel [30] found that the average EMGs of masticatory muscles in normal people without TMDs was 1.5µV, 1.6µV, 1.3µV, and 1.2µV respectively, and patients with TMD might have a higher EMG of masticatory muscles in MPP positions. In our research, the resting potential of TA in TMD patients before the treatment was consistent with the conclusion, but the resting potential of MM tended to be lower than the results of Scopel’s. The possible reason is that the patients suffered "disuse atrophy" of the masseter muscle due to the long-term chewing dysfunction caused by TMD, thus reducing the corresponding electrophysiological activities of muscles. After the treatment, the EMGs of bilateral temporal muscles tended to decrease and bilateral masticatory muscles tended to increase during MPP. Pinho [31] measured the EMG of patients with and without TMD in the mandibular rest position, they found that the average EMG of the group without TMD at the mandibular rest position was 1.92 ± 1.20 µV and 2.52 ± 1.25 µV in TMD group. Scopel [30] also found that the EMG values of bilateral TAs and MMs in TMD patients decreased significantly after wearing the splint during MPP, the difference was statistically significant. In this research, the EMG of temporal muscles decreased in the same way as above. However, the MM EMG increased by 0.019 µV and 0.061 µV respectively after the completion of splint treatment, which was closer to the EMG of normal people without TMD (1.3 µV and 1.2 µV), thus better confirming our hypothesis. In the research, when patients were in the maximum voluntary clench, the EMGs of bilateral anterior temporalis and masseter muscles are 66.290 µV, 76.774 µV, 83.097 µV, 82.968 µV respectively before the treatment. Tartaglia [32] found that the average EMG of the masseter muscle and temporal muscle of the healthy subjects during MVC was 131.7µV, which was significantly higher than the normal mean value in our study, the reason may be the decrease of the activity of the corresponding masticatory muscle, due to the pain of TMD patients, which leads to the weakening of masticatory function, of course, the influence of occlusal factors on the masticatory muscle is also not excluded here. After the treatment, the EMG of bilateral temporal muscles tended to decrease and bilateral masticatory muscles tended to increase during MVC. Pinho [31] also measured the EMG of patients with and without TMD during MVC, and the average EMG of the group without TMD during MVC was 110.30 ± 82.97 µV, and that of the group with TMD was 66.77 ± 35.22 µV. The conclusion of Tartaglia [32] was also consistent with the conclusion above, they measured the EMG of the masseter muscle and temporal muscle during MVC in TMD patients and healthy subjects, and they found that the mean EMG of the masseter muscle and temporal muscle during MVC was significantly higher in the control group (131.7µV) than in the group with TMD (88.7-117.6µV). In other words, the EMG of masseter muscle and temporal muscle in the patients without TMD was higher than that in the patients with TMD during MVC. In our research, the decease of TA was not consistent with the early research, however, Ferrario [33] found that under the same occlusal load, when the EMG activity of bilateral TAs was greater than that of MMs, it might cause more loads on TMJ, thus causing discomfort and even TMD. Interestingly, in our research, the decreasing trend of bilateral TAs and the increasing trend of MMs may release the load on the TMJ, accounting for relieving the symptoms and signs of TMD patients. 5 Conclusion IMS stabilization splint is one of efficient reversible treatments for TMD which can relieve and even eliminate TMD symptoms, especially for the ease of pain and corrective to jaw movement disorder, but still slightly inferior in the treatment of joint noise. With the use of IMS stabilization splint, the condyle has the tendency of moving forward and outward of TMD patients, and there may be some rotation movement of condyle, and bilateral TMJ condyles don’t have the same movement, which is pretty personalized. IMS stabilization splint may ease even cure the TMD by removing the masticatory muscle disorders, terminating the masticatory muscles antagonism between bad function so as to make them function in harmony with each other. The further sublimation also needs a large number of randomized controlled trials to comprehensively evaluate the curative effect by combining the methods of MRI, spiral CT, Cadiax (computer aided diagnosis axiogragh), mandibular movement trace, joint noise record, T-scan and 3D photography. Abbreviations TMD Temporomandibular Disorders IMS Individual musculoskeletally stable position MSP Musculoskeletally stable position CR Centric Relation MI Maximum intercusp CBCT Cone-Beam Computed Tomography sEMG Surface Electromyogram TA Antirior temporalis MM Masseter muscle MPP Mandibular postural position ICP Intercuspal position MVC Maximum voluntary clench MRI Magnetic resonance imaging Declarations Acknowledgements We thank all the members who contributed to this study. Author contributions ZZ, XL 2 , BS and LT were involved in the conception of the study and designed the study. ZZ and XL 1 are responsible for data collection. Then ZZ analyzed data. ZZ and XL 1 drafted the primary manuscript, XL 2 , BS and LT revised and approved the final manuscript. Finally, all authors have read and approved the manuscript. Funding The study received no funding. Availability of data and materials The data presented in this study are available on reasonable request from the corresponding author. Ethics approval and consent to participate The volunteer provided written informed consent and agreed to use their data for research and journal publication. This study was approved by the Ethics Committee of West China Hospital of Stomatology Institutional Review Board of Sichuan University (reference number WCHSIRB-D-2016-073) and performed in accordance with the relevant guidelines and regulations. Consent for publication The written informed consent for publication was obtained from the patients to publish all clinical date and any accompanying images and also a written consent to publish this information was obtained from study participants. Competing interests The authors declare that they have no competing interests. References Yap AU, Zhang MJ, Cao Y, Lei J, Fu KY: Comparison of psychological states and oral health-related quality of life of patients with differing severity of temporomandibular disorders . J Oral Rehabil 2022, 49 (2):177-185. Dworkin SF, LeResche L: Research diagnostic criteria for temporomandibular disorders: review, criteria, examinations and specifications, critique . J Craniomandib Disord 1992, 6 (4):301-355. De Boever JA, Carlsson GE, Klineberg IJ: Need for occlusal therapy and prosthodontic treatment in the management of temporomandibular disorders. Part I. Occlusal interferences and occlusal adjustment . J Oral Rehabil 2000, 27 (5):367-379. Michelotti A, Iodice G: The role of orthodontics in temporomandibular disorders . J Oral Rehabil 2010, 37 (6):411-429. Roth RH, Rolfs DA: Functional occlusion for the orthodontist. Part II . J Clin Orthod 1981, 15 (2):100-123. Roth RH: Occlusion and condylar position . Am J Orthod Dentofacial Orthop 1995, 107 (3):315-318. Okeson JP: Management of temporomandibular disorders and occlusion. , 7th edn: St. Louis: Elsevier Medicine; 2013. Khan MT, Verma SK, Maheshwari S, Zahid SN, Chaudhary PK: Neuromuscular dentistry: Occlusal diseases and posture . J Oral Biol Craniofac Res 2013, 3 (3):146-150. Corte-Real A, Abreu J, Figueiredo JP, Nunes T: Temporomandibular trauma and reflections on personal evaluation . Forensic Sci Med Pathol 2023. Dawson PE: Functional Occulsion from TMJ to Smile Design . J Oral Health Journal 2007. Fricton JR, Schiffman EL: Reliability of a craniomandibular index . J Dent Res 1986, 65 (11):1359-1364. Derogatis L: SCL-90-R: Administration, scoring and procedures manual for the Revised version. ; 1977. Fricton JR, Schiffman EL: The craniomandibular index: validity . J Prosthet Dent 1987, 58 (2):222-228. Kamelchuk LS, Grace MG, Major PW: Post-imaging temporomandibular joint space analysis . Cranio 1996, 14 (1):23-29. Ikeda K, Kawamura A, Ikeda R: Assessment of optimal condylar position in the coronal and axial planes with limited cone-beam computed tomography . J Prosthodont 2011, 20 (6):432-438. Zhang P, Ge Y, Zhang J, Xu W: Orthodontic treatment improves magnetic resonance imaging features and quality of life in adult patients with temporomandibular disorders . Am J Transl Res 2023, 15 (5):3723-3730. Kuttila M, Le Bell Y, Savolainen-Niemi E, Kuttila S, Alanen P: Efficiency of occlusal appliance therapy in secondary otalgia and temporomandibular disorders . Acta Odontol Scand 2002, 60 (4):248-254. Gavish A, Winocur E, Ventura YS, Halachmi M, Gazit E: Effect of stabilization splint therapy on pain during chewing in patients suffering from myofascial pain . J Oral Rehabil 2002, 29 (12):1181-1186. Leite WB, Oliveira ML, Ferreira IC, Anjos CF, Barbosa MA, Barbosa AC: Effects of 4-Week Diacutaneous Fibrolysis on Myalgia, Mouth Opening, and Level of Functional Severity in Women With Temporomandibular Disorders: A Randomized Controlled Trial . J Manipulative Physiol Ther 2020, 43 (8):806-815. Brooks SL, Brand JW, Gibbs SJ, Hollender L, Lurie AG, Omnell KA, Westesson PL, White SC: Imaging of the temporomandibular joint: a position paper of the American Academy of Oral and Maxillofacial Radiology . Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1997, 83 (5):609-618. Weinberg LA: Role of condylar position in TMJ dysfunction-pain syndrome . J Prosthet Dent 1979, 41 (6):636-643. Major PW, Kinniburgh RD, Nebbe B, Prasad NG, Glover KE: Tomographic assessment of temporomandibular joint osseous articular surface contour and spatial relationships associated with disc displacement and disc length . Am J Orthod Dentofacial Orthop 2002, 121 (2):152-161. Zhang ZL, Cheng JG, Li G, Zhang JZ, Zhang ZY, Ma XC: Measurement accuracy of temporomandibular joint space in Promax 3-dimensional cone-beam computerized tomography images . Oral Surg Oral Med Oral Pathol Oral Radiol 2012, 114 (1):112-117. Mongini F: Abnormalities in condylar and positions.in:Silberg,Clark GT,editers.Abnormal jaw mechanics,diagnosis and treatment. In: Chicago:Quintessence,. vol. 30; 1980. Westesson PL, Kurita K, Eriksson L, Katzberg RW: Cryosectional observations of functional anatomy of the temporomandibular joint . Oral Surg Oral Med Oral Pathol 1989, 68 (3):247-251. Sahler LG, Morris TW, Katzberg RW, Tallents RH: Microangiography of the rabbit temporomandibular joint in the open and closed jaw positions . J Oral Maxillofac Surg 1990, 48 (8):831-834. Witkowska A: An outline of the history of electromyography. The significance of surface electromyography in neurophysiological diagnosis. . Nowiny Lekarskie 2008, 77 (3):227-230. Wozniak K, Piatkowska D, Lipski M, Mehr K: Surface electromyography in orthodontics - a literature review . Med Sci Monit 2013, 19 :416-423. Visser A, McCarroll RS, Naeije M: Masticatory muscle activity in different jaw relations during submaximal clenching efforts . J Dent Res 1992, 71 (2):372-379. Scopel V, Alves da Costa GS, Urias D: An electromyographic study of masseter and anterior temporalis muscles in extra-articular myogenous TMJ pain patients compared to an asymptomatic and normal population . Cranio 2005, 23 (3):194-203. Pinho JC, Caldas FM, Mora MJ, Santana-Penin U: Electromyographic activity in patients with temporomandibular disorders . J Oral Rehabil 2000, 27 (11):985-990. Tartaglia GM, Moreira Rodrigues da Silva MA, Bottini S, Sforza C, Ferrario VF: Masticatory muscle activity during maximum voluntary clench in different research diagnostic criteria for temporomandibular disorders (RDC/TMD) groups . Man Ther 2008, 13 (5):434-440. Ferrario VF, Sforza C: Biomechanical model of the human mandible in unilateral clench: distribution of temporomandibular joint reaction forces between working and balancing sides . J Prosthet Dent 1994, 72 (2):169-176. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 13 Sep, 2024 Read the published version in BMC Oral Health → Version 1 posted Editorial decision: Revision requested 10 Jul, 2024 Reviews received at journal 07 Jul, 2024 Reviews received at journal 02 Jul, 2024 Reviewers agreed at journal 28 Jun, 2024 Reviewers agreed at journal 23 Jun, 2024 Reviewers agreed at journal 21 Jun, 2024 Reviewers agreed at journal 21 Jun, 2024 Reviewers invited by journal 21 Jun, 2024 Editor invited by journal 19 Jun, 2024 Editor assigned by journal 18 Jun, 2024 Submission checks completed at journal 18 Jun, 2024 First submitted to journal 14 Jun, 2024 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-4582957","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":322448846,"identity":"ae0031cf-159e-420c-a206-e070b0a9f395","order_by":0,"name":"Zhi Zhang","email":"","orcid":"","institution":"State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Cleft Lip and Palate Surgery, West China Hospital of Stomatology, Sichuan University","correspondingAuthor":false,"prefix":"","firstName":"Zhi","middleName":"","lastName":"Zhang","suffix":""},{"id":322448847,"identity":"8bfd551e-3b80-487d-890e-8812e2f6b685","order_by":1,"name":"Xiao Luo","email":"","orcid":"","institution":"State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Cleft Lip and Palate Surgery, West China Hospital of Stomatology, Sichuan University","correspondingAuthor":false,"prefix":"","firstName":"Xiao","middleName":"","lastName":"Luo","suffix":""},{"id":322448848,"identity":"51a3da3b-743b-409f-8178-3d9265271266","order_by":2,"name":"Xiaoqing Li","email":"","orcid":"","institution":"State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Temporomandibular Joint, West China Hospital of Stomatology, Sichuan University","correspondingAuthor":false,"prefix":"","firstName":"Xiaoqing","middleName":"","lastName":"Li","suffix":""},{"id":322448849,"identity":"a63c5cfb-b5c9-4803-9c02-066b0e4b3f8b","order_by":3,"name":"Bing Shi","email":"","orcid":"","institution":"State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Cleft Lip and Palate Surgery, West China Hospital of Stomatology, Sichuan University","correspondingAuthor":false,"prefix":"","firstName":"Bing","middleName":"","lastName":"Shi","suffix":""},{"id":322448850,"identity":"379fd39c-344c-4064-98f2-dc5dd1f43cc7","order_by":4,"name":"Lijun Tan","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAwklEQVRIiWNgGAWjYBACfmb2AwYfKiTq+4nWItnOk1A444wF48wGYrUYnGcw+MzbVsG44QDR1hxmSNzM2ybBbHw8eQPDj4pthHUwNjMeNpxzToLN7MyzAsaeM7cJa2FmZkgzeFMmwWN2I8eAmbGNCC1szAzmP3jYJCSMZxCrhYeZwcCQp03CwECCWC0SzDwJhjPOSCRIAP1ykCi/2J8/DorKugT+9uSND35UEKEFCSQYHCBJPVgLqTpGwSgYBaNghAAAR+M7OsYje2sAAAAASUVORK5CYII=","orcid":"","institution":"State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University","correspondingAuthor":true,"prefix":"","firstName":"Lijun","middleName":"","lastName":"Tan","suffix":""}],"badges":[],"createdAt":"2024-06-14 15:15:01","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4582957/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4582957/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12903-024-04864-9","type":"published","date":"2024-09-13T15:57:59+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":60448855,"identity":"6581e905-6040-4a71-a59c-3487059dce21","added_by":"auto","created_at":"2024-07-16 22:17:54","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":4119633,"visible":true,"origin":"","legend":"\u003cp\u003eManufacturing process and application of IMS stabilization. \u003cstrong\u003eA\u003c/strong\u003e=0.8mm hard acrylic diaphragm molding; \u003cstrong\u003eB\u003c/strong\u003e=The appliance was trimmed; \u003cstrong\u003eC\u003c/strong\u003e=The adjustment of the splint is completed; \u003cstrong\u003eD\u003c/strong\u003e=Frontal view of IMS stabilization splint positioned in the mouth; \u003cstrong\u003eE\u003c/strong\u003e=Frontal views during CR (Centric Relation) position, incisors guidance in protrusive movement and canine guidance in lateral movement according to the functional occlusion with IMS stabilization splint positioned in the mouth (from left to right); \u003cstrong\u003eF\u003c/strong\u003e=Right lateral views; \u003cstrong\u003eG\u003c/strong\u003e=Left lateral views\u003c/p\u003e","description":"","filename":"figure121.png","url":"https://assets-eu.researchsquare.com/files/rs-4582957/v1/038b98a5142d92fae18ff9d6.png"},{"id":60447831,"identity":"c486a884-d45b-47a7-92f2-10da82ba7187","added_by":"auto","created_at":"2024-07-16 22:09:54","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":1485191,"visible":true,"origin":"","legend":"\u003cp\u003eMethods for measuring joint space. \u003cstrong\u003eA\u003c/strong\u003e=The anterior, upper and posterior joint spaces were measured according to Kamelchuk [14]; \u003cstrong\u003eB\u003c/strong\u003e=The outer and inner joint spaces were measured according to Ikeda [15]\u003c/p\u003e","description":"","filename":"figure213.png","url":"https://assets-eu.researchsquare.com/files/rs-4582957/v1/304897a3e49798fa02b31780.png"},{"id":60447836,"identity":"20de4b72-7e12-401a-b0bd-574878070b23","added_by":"auto","created_at":"2024-07-16 22:09:54","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":2743854,"visible":true,"origin":"","legend":"\u003cp\u003eEMG during mandibular posture position (MPP). The average values of EMG were in the small box on the right of each muscle (LTA: Left Anterior Temporalis; RTA: Right Anterior Temporalis; LMM: Left Masseter Muscle; RMM: Right Masseter Muscle). \u003cstrong\u003eA\u003c/strong\u003e=Before treatment; \u003cstrong\u003eB\u003c/strong\u003e=After treatment\u003c/p\u003e","description":"","filename":"Onlinefigure3.png","url":"https://assets-eu.researchsquare.com/files/rs-4582957/v1/973fb7cf555bbe1e40986898.png"},{"id":60447832,"identity":"8c153a56-f7fa-46f6-bf05-884209445397","added_by":"auto","created_at":"2024-07-16 22:09:54","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":772434,"visible":true,"origin":"","legend":"\u003cp\u003eEMG during maximum voluntary clench (MVC). \u003cstrong\u003eA\u003c/strong\u003e=Before treatment; \u003cstrong\u003eB\u003c/strong\u003e=After treatment. The EMG of LTA and RTA were in harmony after the treatment, Anterior Temporalis decreased and Masseter Muscle increased\u003c/p\u003e","description":"","filename":"Onlinefigure4.png","url":"https://assets-eu.researchsquare.com/files/rs-4582957/v1/ffbedc3d4266909f656e9e13.png"},{"id":60447835,"identity":"23a73b09-04f5-4a86-9d53-9483bc1b486f","added_by":"auto","created_at":"2024-07-16 22:09:54","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":69335,"visible":true,"origin":"","legend":"\u003cp\u003eComparisons of Fricton Index in 31 patients with TMDs before and after treatment (* means \u003cem\u003ep \u003c/em\u003e\u0026lt; 0.05), MM: Mandibular Movement; JN: Joint Noise; JP: Joint Palpation; DI: Dysfunction Index; PI: Palpation Index; CMI: Craniomandibular Index\u003c/p\u003e","description":"","filename":"Onlinefigure5.png","url":"https://assets-eu.researchsquare.com/files/rs-4582957/v1/67aa54335bb636e7038d38fd.png"},{"id":60448853,"identity":"4af4eb64-6aba-4595-9640-f7823105fcd0","added_by":"auto","created_at":"2024-07-16 22:17:54","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":411621,"visible":true,"origin":"","legend":"\u003cp\u003eMeasurement results of TMJ spaces before and after treatment (* means\u003cem\u003e p \u003c/em\u003e\u0026lt; 0.05). \u003cstrong\u003eA\u003c/strong\u003e=Measurement results of the left TMJ space in 31 patients before and after treatment; \u003cstrong\u003eB\u003c/strong\u003e=Measurement results of right TMJ space before and after treatment; \u003cstrong\u003eC\u003c/strong\u003e=Measurement results of bilateral TMJ space before and after treatment\u003c/p\u003e","description":"","filename":"Onlinefigure6.png","url":"https://assets-eu.researchsquare.com/files/rs-4582957/v1/359cab60003bd3874213c9f8.png"},{"id":60449110,"identity":"abba36da-2a30-4a02-9c81-30765b6d0a88","added_by":"auto","created_at":"2024-07-16 22:25:54","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":262672,"visible":true,"origin":"","legend":"\u003cp\u003eComparisons of EMG before and after treatment (* means \u003cem\u003ep \u003c/em\u003e\u0026lt; 0.05). \u003cstrong\u003eA\u003c/strong\u003e=Comparisons of EMG in MPP before and after treatment; \u003cstrong\u003eB\u003c/strong\u003e=Comparisons of EMG in MVC before and after treatment.\u003c/p\u003e","description":"","filename":"Onlinefigure7.png","url":"https://assets-eu.researchsquare.com/files/rs-4582957/v1/50d2177ddd72fac6c0dc0af5.png"},{"id":64619235,"identity":"06787d53-f7c2-4589-891f-12d66bb80a17","added_by":"auto","created_at":"2024-09-16 16:13:09","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":9961350,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4582957/v1/8eef2ea1-3541-443c-aa4c-55fed5e43598.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"The preliminary study of the effects of individual musculoskeletally stable position in the treatment of temporomandibular disorders","fulltext":[{"header":"1 Background","content":"\u003cp\u003eTMD (Temporomandibular Joint Disorders) is a common oral-maxillofacial disease [1]. Epidemiology shows that, approximately 75% of the world\u0026rsquo;s population has one sign and at least 33% has one symptom of TMDs [2]. TMDs are dysfunctions of muscle groups and bones in TMJ (Temporomandibular Joint) areas, main symptoms of TMDs are pains in masticatory muscles around TMJs and (or) inside TMJs themselves, which in turn seriously affect the patients\u0026rsquo; life qualities and social behaviors. According to the classification of risk factors by de Boever [3], occlusal patterns, neuromuscular system disorders, social and emotional statuses, etc, tend to be predominant in TMD occurrences. Unfortunately, a direct correlation between psychophysiological or psychological accounts and TMD is not found yet [4], thus reliable and effective treatments to TMD are not available currently. As to the treatment principle of TMD, reversible comprehensive conservative treatment was taken at first, such as splint therapy and psychotherapy; the final choice is irreversible treatment, including selected grinding, fixed prosthesis treatment, orthognathic surgery and orthodontic treatment.\u003c/p\u003e \u003cp\u003eClinicians will not start orthodontic treatments until the patients\u0026rsquo; TMJs are in a better condition, condyles have been repositioned following the changes of relationships between mandibles and maxillae with the method of RW (Roth Williams) philosophy [5, 6]. The most orthopedically stable joint position which exists when the condyles in the most superoanterior positions of the articular fossae, resting against the posterior articular slopes with discs properly interposed. The condyle position when the elevator muscles activated with no occlusal influences is therefore considered to be the most MSP (musculoskeletally stable position) of the mandible [7] and is also the theoretical foundation of RW philosophy. If the condyles are repositioned in MSP by splints, the maximum intercuspal position is formed, healthy TMJ, coordinated occlusion and facial aesthetics could be obtained via this approach in order to achieve long-term stability of orthodontics. However, there may are still a few flaws in RW philosophy: (i) For clinicians, it is difficult to get condyles in the most superoanterior position, so the repeatability cannot be guaranteed; (ii) The most superoanterior position may not be the suitable position since TMJ, muscles, ligaments, facial connections, as well as neural and circulatory innervations are all intimately related[8]. (iii) Acute pain may be caused by huge positional changes between the articular discs and the condyles, bad emotional status is still a significant risk factor leading to TMD [9].\u003c/p\u003e \u003cp\u003eStomatognathic system, an integral component of the upper body, is basically composed of the head, neck and shoulder girdle. Clinicians should not treat every patient with the same approach, thus IMS (Individual Musculoskeletally Stable) position was innovatively proposed which is different from Dawson\u0026rsquo;s manual reposition [10]. IMS position may not be the most superoanterior position, however, it may be the position where TMJ, muscles, ligaments, facial connections and nerve functions are in harmony corresponding to the individual anatomy.\u003c/p\u003e \u003cp\u003eThe aim of this research is to conduct a preliminary understanding of the IMS splint therapeutic effect by evaluation means of Fricton Index [11], CBCT (Cone-beam Computerized Tomography) and sEMG (surface Electromyogram). Specifically, we seek to bring into focus the result on the mandibular condyle position in order to break a new path to treat TMD, with both clinical effect and the balance of the stomatognathic system taken into consideration.\u003c/p\u003e"},{"header":"2 Methods","content":"\u003cp\u003e \u003cb\u003eParticipants\u003c/b\u003e \u003c/p\u003e \u003cp\u003eA group of 31 consecutive patients with TMD (joint structure disorder and masticatory muscle disorders) were identified as members for the study inclusion. All patients received examination and treatment for TMDs at the Department of TMJ, West China Hospital of Stomatology, Sichuan University from 2019 to 2022. The research was approved by the Medical Ethics Committee of West China Hospital of Stomatology, Sichuan University (No. WCHSIRB-D-2016-073). The initial TMD diagnosis was based on cone beam computed tomography (CBCT) in combination with clinical findings obtained from our standardized TMJ clinical examinations at the Department of TMJ. Radiological pathological finding was defined as conditions deviating from the normal TMJ space on two-dimensional CBCT cuts. What\u0026rsquo;s more, the initial TMD diagnosis was made based on clinical examinations, orofacial symptoms were of great importance, and Fricton Index was used in this study for assessment.\u003c/p\u003e \u003cp\u003e \u003cb\u003eInclusion and exclusion criteria\u003c/b\u003e \u003c/p\u003e \u003cp\u003eThe inclusion criteria were: (i) TMD diagnosis according to the criteria of American Dental Association[7]; (ii) no inflammation in the mandibular condyle according to the examination of CBCT; (iii) patients were capable of understanding our treatment and willing to co-operate with us.\u003c/p\u003e \u003cp\u003eThe exclusion criteria were: (i) patients had been treated with occlusal reconstruction in the way of orthodontics and/or prosthetics; (ii) there was inflammation in the mandibular condyle according to the examination of CBCT; (iii) the score of Symptom Checklist 90 (SCL-90) [12] was more than 160; (iv) patients with TMJ trauma or other systemic disease; (v) patients failed to accept orthognathic surgery which was considered possible.\u003c/p\u003e \u003cp\u003e \u003cb\u003eThe usage of Stabilization splint\u003c/b\u003e \u003c/p\u003e \u003cp\u003ePatients were asked to bite the cotton roll for at least 20 minutes in order to smash the procedure of masticatory muscles, and then they closed their mouth as freely as they can in order to find a comfortable position, both in muscles and bones, during which the bite recording was made. The stabilization splint used in our study was fabricated from impression of upper dental arch and a silicone rubber bite recording of the IMS position. The splint was fabricated as a \u0026ldquo;flat\u0026rdquo; splint with no impression for occluding guidance in the posterior teeth, however, there should be incisors guidance in protrusive movement and canine guidance in lateral movement according to the functional occlusion (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Patients were instructed to wear the splint all day long except when they were brushing their teeth or having more serious clinical symptoms. The splint was ground individually, based on functional occlusion, weekly in the first month, then monthly in the next months until stable. Additionally, participants were comforted in each visit.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cb\u003eClinical curative effect\u003c/b\u003e \u003c/p\u003e \u003cp\u003eAt pre and post-treatment, all patients completed a standardized questionnaire in combination with clinical examinations by one rater. Fricton Index [11, 13] was implied in this study, which was comprised of Dysfunction Index (DI) and Palpation Index (PI), the Craniomandibular Index (CMI) was developed to provide a standardized measure of problems severity in the mandibular movement, TMJ noise, muscle and joint tenderness for use in epidemiological and clinical outcome studies.\u003c/p\u003e \u003cp\u003e \u003cb\u003eTMJ Space Distance\u003c/b\u003e \u003c/p\u003e \u003cp\u003eAt pre and post-treatment, all patients had a radiological examination based on CBCT, Joint-space distances between the condyle and glenoid fossa were divided into anterior, upper and posterior spaces in the sagittal plane according to Kamelchuk [14] and the inner and outer spaces in the coronal plane according to Ikeda [15]. Specific details (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cb\u003eSurface Electromyogram\u003c/b\u003e \u003c/p\u003e \u003cp\u003eAt pre and post-treatment, all patients were tested in the Chewing Function Room, West China Hospital of Stomatology, Sichuan University where it was silent enough and the temperature was between 22\u0026ndash;25℃. Electromyographic devices were applied to the patients in this study (K-7 EMG, Myotronics Noromed, Inc. Kent, WA), and each patient was asked to sit comfortably in an upright chair with eyes slightly closed. The EMG device was used to measure each patient\u0026rsquo;s two paired muscles (anterior temporalis and masseter muscles). Measurements were performed after each patient was asked to assume a resting mandibular position (mandibular posture position, MPP) where the teeth were not touching. Three successive sets of data were obtained and we took the average of them. Then maximum voluntary clench (MVC) position was performed in order to measure the EMG of the muscles with the device by asking each patient to alternately clench his/her teeth maximally three times for two seconds with two seconds of relaxation between each clench period, which was repeated for three times and we took the average of them (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cb\u003eStatistics\u003c/b\u003e \u003c/p\u003e \u003cp\u003ePre and post-treatment outcome variables were compared to themselves by paired Student\u0026rsquo;s t-tests after the data were tested for normal distribution, and \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered significant.\u003c/p\u003e"},{"header":"3 Results","content":"\u003cp\u003eAmong the 31 patients (ranging from 18 through 26 years old, including 7 males and 24 females), 17 were in the group of joint structure disorders, 14 were in the group of masticatory muscle disorders (The treatment time ranged from 6 through 8 months).\u003c/p\u003e \u003cp\u003e \u003cb\u003eClinical curative effect\u003c/b\u003e \u003c/p\u003e \u003cp\u003eThe mandibular movement score was 2.45, the joint palpation score was 0.35, the dysfunction index was 0.14, the craniomandibular index score was 0.10 and there was statistical difference (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05); the joint noise score (1.03) had the decreasing trend, however, there was no statistical difference (\u003cem\u003ep\u003c/em\u003e \u0026gt; 0.05) (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparisons of Fricton Index in patients with TMD before and after treatment (n\u0026thinsp;=\u0026thinsp;31) \u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e\u0026plusmn;s\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eScales\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePre-treatment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePost-treatment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDifference value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMandibular Movement (MM)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e5.45\u0026thinsp;\u0026plusmn;\u0026thinsp;2.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.45\u0026thinsp;\u0026plusmn;\u0026thinsp;1.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e-3.00\u0026thinsp;\u0026plusmn;\u0026thinsp;2.54\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e-6.568\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eJoint Noise (JN)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e1.42\u0026thinsp;\u0026plusmn;\u0026thinsp;1.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e1.03\u0026thinsp;\u0026plusmn;\u0026thinsp;0.84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e-0.39\u0026thinsp;\u0026plusmn;\u0026thinsp;1.23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e-1.753\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.090\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eJoint Palpation (JP)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e1.03\u0026thinsp;\u0026plusmn;\u0026thinsp;0.84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.35\u0026thinsp;\u0026plusmn;\u0026thinsp;0.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e-0.67\u0026thinsp;\u0026plusmn;\u0026thinsp;0.98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e-3.851\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eDysfunction Index (DI)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.30\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.14\u0026thinsp;\u0026plusmn;\u0026thinsp;0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e-0.16\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e-7.749\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePalpation Index (PI)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.13\u0026thinsp;\u0026plusmn;\u0026thinsp;0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.06\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e-0.07\u0026thinsp;\u0026plusmn;\u0026thinsp;0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e-7.228\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCraniomandibular Index (CMI)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.21\u0026thinsp;\u0026plusmn;\u0026thinsp;0.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.10\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e-0.12\u0026thinsp;\u0026plusmn;\u0026thinsp;0.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e-9.218\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cb\u003eTMJ Space Distance\u003c/b\u003e \u003c/p\u003e \u003cp\u003eThe anterior space of the left temporomandibular joint became smaller (the difference is -0.61\u0026thinsp;\u0026plusmn;\u0026thinsp;0.91 mm), and the difference was statistically significant (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05); the posterior, upper, inner and outer space became bigger, and the change of the posterior space was the most obvious (0.28\u0026thinsp;\u0026plusmn;\u0026thinsp;1.42 mm) while the change of the outer space was the smallest (0.04\u0026thinsp;\u0026plusmn;\u0026thinsp;1.38 mm), however, none of them was statistically different (\u003cem\u003ep\u003c/em\u003e \u0026gt; 0.05) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe anterior space of the right temporomandibular joint became smaller (the difference is -0.12\u0026thinsp;\u0026plusmn;\u0026thinsp;0.90 mm) which had no statistical significant difference (\u003cem\u003ep\u003c/em\u003e \u0026gt; 0.05); the posterior, upper, inner and outer space all became bigger, and the change of the inner space was the most obvious (0.32\u0026thinsp;\u0026plusmn;\u0026thinsp;0.81 mm) which had significant statistical difference (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05), however, the rest of them had no statistical difference (\u003cem\u003ep \u0026gt;\u003c/em\u003e 0.05). The posterior and the upper space had smaller changes (0.11\u0026thinsp;\u0026plusmn;\u0026thinsp;0.70 mm and 0.05\u0026thinsp;\u0026plusmn;\u0026thinsp;1.01 mm respectively) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe anterior spaces of both sides of the TMJs became smaller (the difference is -0.36\u0026thinsp;\u0026plusmn;\u0026thinsp;0.93 mm), which had significant statistical differences (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05); the posterior, upper, inner and outer space all became bigger, and the change of the inner space was the most obvious (0.26\u0026thinsp;\u0026plusmn;\u0026thinsp;0.80 mm) which had the significant statistical difference (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05), however, the rest of them have no statistical difference (\u003cem\u003ep\u003c/em\u003e \u0026gt; 0.05), the outer space had the smallest change (0.08\u0026thinsp;\u0026plusmn;\u0026thinsp;1.14 mm) (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparisons of the left and the right temporomandibular joint spaces before and after treatment (n\u0026thinsp;=\u0026thinsp;31) \u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e\u0026plusmn;s, mm\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eSpace\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePre-treatment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePost-treatment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eDifference value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e \u003cp\u003e\u003cb\u003eLeft\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eAnterior space\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.70\u0026thinsp;\u0026plusmn;\u0026thinsp;0.79\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e2.09\u0026thinsp;\u0026plusmn;\u0026thinsp;0.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e-0.61\u0026thinsp;\u0026plusmn;\u0026thinsp;0.91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e-3.72\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003ePosterior space\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.66\u0026thinsp;\u0026plusmn;\u0026thinsp;1.24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e2.95\u0026thinsp;\u0026plusmn;\u0026thinsp;1.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e0.28\u0026thinsp;\u0026plusmn;\u0026thinsp;1.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.274\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eUpper space\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.56\u0026thinsp;\u0026plusmn;\u0026thinsp;0.98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e2.78\u0026thinsp;\u0026plusmn;\u0026thinsp;1.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e0.22\u0026thinsp;\u0026plusmn;\u0026thinsp;1.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.240\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eInner space\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.32\u0026thinsp;\u0026plusmn;\u0026thinsp;0.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e2.52\u0026thinsp;\u0026plusmn;\u0026thinsp;0.69\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e0.20\u0026thinsp;\u0026plusmn;\u0026thinsp;0.80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.181\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eOuter space\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.57\u0026thinsp;\u0026plusmn;\u0026thinsp;1.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e2.61\u0026thinsp;\u0026plusmn;\u0026thinsp;1.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e0.04\u0026thinsp;\u0026plusmn;\u0026thinsp;1.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.877\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e \u003cp\u003e\u003cb\u003eRight\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eAnterior space\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.71\u0026thinsp;\u0026plusmn;\u0026thinsp;0.66\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e2.60\u0026thinsp;\u0026plusmn;\u0026thinsp;0.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e-0.12\u0026thinsp;\u0026plusmn;\u0026thinsp;0.90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e-0.74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.466\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003ePosterior space\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.02\u0026thinsp;\u0026plusmn;\u0026thinsp;0.64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e2.13\u0026thinsp;\u0026plusmn;\u0026thinsp;0.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e0.11\u0026thinsp;\u0026plusmn;\u0026thinsp;0.70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.89\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.383\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eUpper space\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.61\u0026thinsp;\u0026plusmn;\u0026thinsp;1.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e2.66\u0026thinsp;\u0026plusmn;\u0026thinsp;0.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e0.05\u0026thinsp;\u0026plusmn;\u0026thinsp;1.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.780\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eInner space\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.47\u0026thinsp;\u0026plusmn;\u0026thinsp;0.91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e2.79\u0026thinsp;\u0026plusmn;\u0026thinsp;0.64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e0.32\u0026thinsp;\u0026plusmn;\u0026thinsp;0.81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e2.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.039\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eOuter space\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.39\u0026thinsp;\u0026plusmn;\u0026thinsp;0.62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e2.52\u0026thinsp;\u0026plusmn;\u0026thinsp;0.70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e0.13\u0026thinsp;\u0026plusmn;\u0026thinsp;0.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.412\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparisons of bilateral temporomandibular joint spaces before and after treatment (n\u0026thinsp;=\u0026thinsp;62) \u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e\u0026plusmn;s, mm\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSpace\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePre-treatment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePost-treatment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDifference value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAnterior space\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e2.71\u0026thinsp;\u0026plusmn;\u0026thinsp;0.73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.34\u0026thinsp;\u0026plusmn;\u0026thinsp;0.73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e-0.36\u0026thinsp;\u0026plusmn;\u0026thinsp;0.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e-3.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.003\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePosterior space\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e2.34\u0026thinsp;\u0026plusmn;\u0026thinsp;1.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.54\u0026thinsp;\u0026plusmn;\u0026thinsp;0.96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.20\u0026thinsp;\u0026plusmn;\u0026thinsp;1.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.167\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eUpper space\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e2.58\u0026thinsp;\u0026plusmn;\u0026thinsp;1.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.71\u0026thinsp;\u0026plusmn;\u0026thinsp;0.80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.14\u0026thinsp;\u0026plusmn;\u0026thinsp;1.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.294\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eInner space\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e2.40\u0026thinsp;\u0026plusmn;\u0026thinsp;0.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.65\u0026thinsp;\u0026plusmn;\u0026thinsp;0.68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.26\u0026thinsp;\u0026plusmn;\u0026thinsp;0.80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.015\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eOuter space\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e2.48\u0026thinsp;\u0026plusmn;\u0026thinsp;0.86\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.57\u0026thinsp;\u0026plusmn;\u0026thinsp;0.92\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.08\u0026thinsp;\u0026plusmn;\u0026thinsp;1.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.564\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cb\u003eSurface Electromyogram\u003c/b\u003e \u003c/p\u003e \u003cp\u003eWhen the TMJs were in the mandibular postural position, the electromyogram of bilateral anterior temporalis decreased, wherein the right side decreased by 0.587\u0026thinsp;\u0026plusmn;\u0026thinsp;1.758 \u0026micro;V which had no statistical difference (\u003cem\u003ep\u003c/em\u003e \u0026gt; 0.05), and the left side decreased by 0.594\u0026thinsp;\u0026plusmn;\u0026thinsp;0.935 \u0026micro;V which had statistical difference (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05); the electromyograms of the left and right masseter muscles increased (0.019\u0026thinsp;\u0026plusmn;\u0026thinsp;0.323 \u0026micro;V and 0.061\u0026thinsp;\u0026plusmn;\u0026thinsp;0.451 \u0026micro;V respectively) which had no statistical difference (\u003cem\u003ep\u003c/em\u003e \u0026gt; 0.05) (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eDuring the maximum voluntary clench, the electromyogram of the left and right anterior temporalis decreased by 3.129\u0026thinsp;\u0026plusmn;\u0026thinsp;29.212 \u0026micro;V and 6.323\u0026thinsp;\u0026plusmn;\u0026thinsp;39.219 \u0026micro;V respectively which had no statistical difference (\u003cem\u003ep\u003c/em\u003e \u0026gt; 0.05); the electromyogram of the left and right masseter muscles increased by 1.613\u0026thinsp;\u0026plusmn;\u0026thinsp;47.623 \u0026micro;V and 2.290\u0026thinsp;\u0026plusmn;\u0026thinsp;63.522 \u0026micro;V respectively which had no statistical difference (\u003cem\u003ep\u003c/em\u003e \u0026gt; 0.05) (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparisons of EMG during MPP before and after treatment (n\u0026thinsp;=\u0026thinsp;31) \u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e\u0026plusmn;s, \u0026micro;V\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMuscles\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePre-treatment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePost-treatment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDifference value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLeft Anterior Temporalis\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e2.023\u0026thinsp;\u0026plusmn;\u0026thinsp;1.008\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e1.429\u0026thinsp;\u0026plusmn;\u0026thinsp;0.440\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e-0.594\u0026thinsp;\u0026plusmn;\u0026thinsp;0.935\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e-3.534\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRight Anterior Temporalis\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e2.752\u0026thinsp;\u0026plusmn;\u0026thinsp;1.872\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.165\u0026thinsp;\u0026plusmn;\u0026thinsp;0.668\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e-0.587\u0026thinsp;\u0026plusmn;\u0026thinsp;1.758\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e-1.859\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.073\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLeft Masseter Muscle\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.797\u0026thinsp;\u0026plusmn;\u0026thinsp;0.266\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.816\u0026thinsp;\u0026plusmn;\u0026thinsp;0.173\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.019\u0026thinsp;\u0026plusmn;\u0026thinsp;0.323\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.334\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.741\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRight Masseter Muscle\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.984\u0026thinsp;\u0026plusmn;\u0026thinsp;0.415\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e1.045\u0026thinsp;\u0026plusmn;\u0026thinsp;0.234\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.061\u0026thinsp;\u0026plusmn;\u0026thinsp;0.451\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.756\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.456\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparisons of EMG during MVC before and after treatment (n\u0026thinsp;=\u0026thinsp;31) \u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e\u0026plusmn;s, \u0026micro;V\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMuscles\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePre-treatment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePost-treatment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDifference value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLeft Anterior Temporalis\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e66.290\u0026thinsp;\u0026plusmn;\u0026thinsp;27.452\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e63.161\u0026thinsp;\u0026plusmn;\u0026thinsp;20.648\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e-3.129\u0026thinsp;\u0026plusmn;\u0026thinsp;29.212\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e-0.696\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.555\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRight Anterior Temporalis\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e76.774\u0026thinsp;\u0026plusmn;\u0026thinsp;36.179\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e70.452\u0026thinsp;\u0026plusmn;\u0026thinsp;25.878\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e-6.323\u0026thinsp;\u0026plusmn;\u0026thinsp;39.219\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e-0.898\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.377\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLeft Masseter Muscle\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e83.097\u0026thinsp;\u0026plusmn;\u0026thinsp;46.180\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e84.710\u0026thinsp;\u0026plusmn;\u0026thinsp;32.964\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e1.613\u0026thinsp;\u0026plusmn;\u0026thinsp;47.623\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.189\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.852\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRight Masseter Muscle\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e82.968\u0026thinsp;\u0026plusmn;\u0026thinsp;63.312\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e85.258\u0026thinsp;\u0026plusmn;\u0026thinsp;52.686\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e2.290\u0026thinsp;\u0026plusmn;\u0026thinsp;63.522\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.201\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.842\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"4 Discussion","content":"\u003cp\u003e \u003cb\u003eClinical curative effect\u003c/b\u003e \u003c/p\u003e \u003cp\u003ePain, joint noise and limited movement are the common symptoms of TMD, and clinical evaluation of its therapeutic effect is always limited to qualitative description stage, such as obvious effect, effective or ineffective, however, descriptive and subjective reports should be avoided to evaluate the degree of TMD dysfunction or evaluate the TMD therapeutic effect. Fricton disorder index was objective and reliable to a certain extent, which could be used in clinical practice to conduct quantitative and objective evaluation of TMD treatment effect [11, 13, 16]. In our research, immediate pain reliefs of 21 patients with TMDs were reported. The splint used in the research was mainly stabilization splint covering the entire dentition of the patient's upper jaw which simulated Roth functional occlusion concept. The stabilization splint had a good application prospect in the treatment of maxillofacial pain by other researches [17, 18]. In this research, 24 patients with TMDs had joint noises before treatment. After 6\u0026ndash;8 months of splint treatment, the joint noises of only 7 patients had disappeared significantly, of which 9 had relieved and 8 had no change. Joint noise mainly indicates bounce, friction and cracking, etc. Bounce was chosen for the research, and there are two pathogenesis, one occurs at the beginning of the opening, which is the anterior disc displacement with reduction, and the other often occurs at the end of the opening with hyper function of pterygoid. In the research, the mandibular movement state of 31 TMD patients had been significantly improved, and the reason may be the separation of upper and lower jaw, the bad muscle memory type of the past was eliminated, then the bad guidance of the musculoskeletal state gradually was eliminated, the open mouth type gradually recovered to be consistent. Moreover, due to the increases of the height between jaws, the negative pressure in the joint cavity was reduced and the adhesive tissue was loosened, thus the mouth opening degree improved. Leite [19] also suggested that the ease of pain of TA maybe a possible potential use of TMDs for mouth opening, our study also found the decrease of sEMG of TA in MPP.\u003c/p\u003e \u003cp\u003e \u003cb\u003eTMJ Space Distance\u003c/b\u003e \u003c/p\u003e \u003cp\u003eCBCT can reflect the bone changes of temporomandibular joint from three-dimensional direction, and the changes of joint space can be observed easier [20]. It was generally believed that condylar displacement may be one of the important imaging manifestations of TMD [21]. Major [22] found that the change of joint space might be associated with the displacement of articular disc to some extent, and the detection of condyle position by CBCT might be used to predict the location of articular discs. Zhang [23] had found that there was no significant statistical difference between the joint spaces measured by CBCT and those measured by actual impression (P\u0026thinsp;=\u0026thinsp;0.305). It can be considered that CBCT has certain reliability and authenticity in measuring temporomandibular joint spaces. The joint space is of great significance in the diagnosis and treatment of TMD, the previous studies showed that the proportion of small posterior space of patients with TMDs was significantly higher than that of asymptomatic controls [24], the possible reason is that smaller posterior spaces may produce more pressure to the double plate areas, which is loose connective tissues that is rich in blood vessels and nerves. On the contrary, when the condyle process moves forward, the vein will be filled to provide nutrition for the joint area [25] [26]. When long-term compression causes dysfunction in the bilateral plate area, signs and symptoms related to TMD may appear.\u003c/p\u003e \u003cp\u003eIkeda [15] had used Kamelchuk method [14] to measure joint spaces in 24 TMJs of 22 healthy people without joint symptoms, and the anterior, posterior and superior joint spaces were 1.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.2mm, 2.1\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3mm and 2.5\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5mm, respectively. In this research, joint spaces were measured in 31 TMD patients before treatment, and the anterior, posterior, and upper joint spaces were 2.71\u0026thinsp;\u0026plusmn;\u0026thinsp;0.73 mm, 2.34\u0026thinsp;\u0026plusmn;\u0026thinsp;1.03 mm and 2.58\u0026thinsp;\u0026plusmn;\u0026thinsp;1.00 mm respectively. The anterior spaces of TMD patients increased significantly while the mean value of the posterior spaces decreased but the difference was not significant, and it may be related to the morphological changes of condyles in TMD patients. Patients in this research might be subject to occlusion interference or early contact. In order to avoid the nerve-muscle damage, the adaptive change was produced, perhaps the reconstruction of condyle. However, symptoms related with TMDs might appear when the change went beyond TMJ physiological tolerance [6].\u003c/p\u003e \u003cp\u003eThe RW-splint treatment showed a certain deviation between the final trend of condyle movement and the position of manipulative reduction of occlusal reconstruction before treatment, which was worth further study. In this research, 31 TMD patients after the treatment of IMS stabilization splint were carried on the statistical analysis in the joint spaces on both sides. It showed that there was a tendency to decrease in the anterior joint space, however, posterior, upper, inner and outer joint space had the trend of increase, the inner space was the most significant. There were different changes on the left and right side of the condylar joint spaces, and the standard deviation was obvious, which indicated that the condylar position had a very high individuation due to the neuromuscular, anatomical physiological and psychological factors. In the term of one individual, bilateral asymmetry of neuromuscular function, asymmetry of condyle morphologies and rotation of condyles would result in the asymmetry of bilateral motion. Although the variation of the bilateral joint spaces is different due to the individual characteristics, the general trend is the reduction of the anterior joint space.\u003c/p\u003e \u003cp\u003e \u003cb\u003eSurface Electromyogram\u003c/b\u003e \u003c/p\u003e \u003cp\u003eElectromyography was the most reliable and objective technique to evaluate muscle functions and efficacy by monitoring muscle potentials in clinical practices [27], which could evaluate the degree and duration of muscle activities. One method is the sEMG (surface electromyography), this non-invasive and painless electrophysiological activity recording the method of muscle requires the electrode as an auxiliary tool, and the non-invasive properties became its most important advantage [28]. The main goal of sEMG is to monitor the electrophysiological signals of muscle fibers in the attached area through the surface electrodes, these signals are the sum of the activities of multiple motor units in this area. Visser [29] conducted statistical analysis on the EMG monitoring values of masseter muscle and temporal muscle in healthy people within 2 days, and the correlation values showed no significant difference or asymmetry. Accurate quantitative analysis of muscle electrophysiological activities by sEMG simplified the quantitative analysis in the oral and maxillary system and provided the possibility of objective evaluations of muscle functions [28].\u003c/p\u003e \u003cp\u003eIn this research, the EMGs of bilateral anterior temporalis and masseter muscles were 2.023 \u0026micro;V, 2.752 \u0026micro;V, 0.797 \u0026micro;V, 0.984 \u0026micro;V respectively when patients are in the mandibular postural position before the treatment. Scopel [30] found that the average EMGs of masticatory muscles in normal people without TMDs was 1.5\u0026micro;V, 1.6\u0026micro;V, 1.3\u0026micro;V, and 1.2\u0026micro;V respectively, and patients with TMD might have a higher EMG of masticatory muscles in MPP positions. In our research, the resting potential of TA in TMD patients before the treatment was consistent with the conclusion, but the resting potential of MM tended to be lower than the results of Scopel\u0026rsquo;s. The possible reason is that the patients suffered \"disuse atrophy\" of the masseter muscle due to the long-term chewing dysfunction caused by TMD, thus reducing the corresponding electrophysiological activities of muscles.\u003c/p\u003e \u003cp\u003eAfter the treatment, the EMGs of bilateral temporal muscles tended to decrease and bilateral masticatory muscles tended to increase during MPP. Pinho [31] measured the EMG of patients with and without TMD in the mandibular rest position, they found that the average EMG of the group without TMD at the mandibular rest position was 1.92\u0026thinsp;\u0026plusmn;\u0026thinsp;1.20 \u0026micro;V and 2.52\u0026thinsp;\u0026plusmn;\u0026thinsp;1.25 \u0026micro;V in TMD group. Scopel [30] also found that the EMG values of bilateral TAs and MMs in TMD patients decreased significantly after wearing the splint during MPP, the difference was statistically significant. In this research, the EMG of temporal muscles decreased in the same way as above. However, the MM EMG increased by 0.019 \u0026micro;V and 0.061 \u0026micro;V respectively after the completion of splint treatment, which was closer to the EMG of normal people without TMD (1.3 \u0026micro;V and 1.2 \u0026micro;V), thus better confirming our hypothesis.\u003c/p\u003e \u003cp\u003eIn the research, when patients were in the maximum voluntary clench, the EMGs of bilateral anterior temporalis and masseter muscles are 66.290 \u0026micro;V, 76.774 \u0026micro;V, 83.097 \u0026micro;V, 82.968 \u0026micro;V respectively before the treatment. Tartaglia [32] found that the average EMG of the masseter muscle and temporal muscle of the healthy subjects during MVC was 131.7\u0026micro;V, which was significantly higher than the normal mean value in our study, the reason may be the decrease of the activity of the corresponding masticatory muscle, due to the pain of TMD patients, which leads to the weakening of masticatory function, of course, the influence of occlusal factors on the masticatory muscle is also not excluded here.\u003c/p\u003e \u003cp\u003eAfter the treatment, the EMG of bilateral temporal muscles tended to decrease and bilateral masticatory muscles tended to increase during MVC. Pinho [31] also measured the EMG of patients with and without TMD during MVC, and the average EMG of the group without TMD during MVC was 110.30\u0026thinsp;\u0026plusmn;\u0026thinsp;82.97 \u0026micro;V, and that of the group with TMD was 66.77\u0026thinsp;\u0026plusmn;\u0026thinsp;35.22 \u0026micro;V. The conclusion of Tartaglia [32] was also consistent with the conclusion above, they measured the EMG of the masseter muscle and temporal muscle during MVC in TMD patients and healthy subjects, and they found that the mean EMG of the masseter muscle and temporal muscle during MVC was significantly higher in the control group (131.7\u0026micro;V) than in the group with TMD (88.7-117.6\u0026micro;V). In other words, the EMG of masseter muscle and temporal muscle in the patients without TMD was higher than that in the patients with TMD during MVC. In our research, the decease of TA was not consistent with the early research, however, Ferrario [33] found that under the same occlusal load, when the EMG activity of bilateral TAs was greater than that of MMs, it might cause more loads on TMJ, thus causing discomfort and even TMD. Interestingly, in our research, the decreasing trend of bilateral TAs and the increasing trend of MMs may release the load on the TMJ, accounting for relieving the symptoms and signs of TMD patients.\u003c/p\u003e"},{"header":"5 Conclusion","content":"\u003cp\u003eIMS stabilization splint is one of efficient reversible treatments for TMD which can relieve and even eliminate TMD symptoms, especially for the ease of pain and corrective to jaw movement disorder, but still slightly inferior in the treatment of joint noise. With the use of IMS stabilization splint, the condyle has the tendency of moving forward and outward of TMD patients, and there may be some rotation movement of condyle, and bilateral TMJ condyles don\u0026rsquo;t have the same movement, which is pretty personalized. IMS stabilization splint may ease even cure the TMD by removing the masticatory muscle disorders, terminating the masticatory muscles antagonism between bad function so as to make them function in harmony with each other. The further sublimation also needs a large number of randomized controlled trials to comprehensively evaluate the curative effect by combining the methods of MRI, spiral CT, Cadiax (computer aided diagnosis axiogragh), mandibular movement trace, joint noise record, T-scan and 3D photography.\u003c/p\u003e "},{"header":"Abbreviations","content":"\u003cp\u003eTMD Temporomandibular Disorders\u003c/p\u003e\n\u003cp\u003eIMS Individual musculoskeletally stable position\u003c/p\u003e\n\u003cp\u003eMSP Musculoskeletally stable position\u003c/p\u003e\n\u003cp\u003eCR Centric Relation\u003c/p\u003e\n\u003cp\u003eMI Maximum intercusp\u003c/p\u003e\n\u003cp\u003eCBCT Cone-Beam Computed Tomography\u003c/p\u003e\n\u003cp\u003esEMG Surface Electromyogram\u003c/p\u003e\n\u003cp\u003eTA Antirior temporalis\u003c/p\u003e\n\u003cp\u003eMM Masseter muscle\u003c/p\u003e\n\u003cp\u003eMPP Mandibular postural position\u003c/p\u003e\n\u003cp\u003eICP Intercuspal position\u003c/p\u003e\n\u003cp\u003eMVC Maximum voluntary clench\u003c/p\u003e\n\u003cp\u003eMRI Magnetic resonance imaging\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe thank all the members who contributed to this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eZZ, XL\u003csup\u003e2\u003c/sup\u003e, BS and LT were involved in the conception of the study and designed the study. ZZ and XL\u003csup\u003e1 \u0026nbsp;\u003c/sup\u003eare responsible for data collection. Then ZZ analyzed data. ZZ and XL\u003csup\u003e1\u003c/sup\u003e drafted the primary manuscript, XL\u003csup\u003e2\u003c/sup\u003e, BS and LT revised and approved the final manuscript. Finally, all authors have read and approved the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study received no funding.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe data presented in this study are available on reasonable request from the corresponding author.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe volunteer provided written informed consent and agreed to use their data for research and journal publication. This study was approved by the Ethics Committee of West China Hospital of Stomatology Institutional Review Board of Sichuan University (reference number WCHSIRB-D-2016-073) and performed in accordance with the relevant guidelines and regulations.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe written informed consent for publication was obtained from the patients to publish all clinical date and any accompanying images and also a written consent to publish this information was obtained from study participants.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eYap AU, Zhang MJ, Cao Y, Lei J, Fu KY: \u003cstrong\u003eComparison of psychological states and oral health-related quality of life of patients with differing severity of temporomandibular disorders\u003c/strong\u003e. \u003cem\u003eJ Oral Rehabil\u0026nbsp;\u003c/em\u003e2022, \u003cstrong\u003e49\u003c/strong\u003e(2):177-185.\u003c/li\u003e\n \u003cli\u003eDworkin SF, LeResche L: \u003cstrong\u003eResearch diagnostic criteria for temporomandibular disorders: review, criteria, examinations and specifications, critique\u003c/strong\u003e. \u003cem\u003eJ Craniomandib Disord\u0026nbsp;\u003c/em\u003e1992, \u003cstrong\u003e6\u003c/strong\u003e(4):301-355.\u003c/li\u003e\n \u003cli\u003eDe Boever JA, Carlsson GE, Klineberg IJ: \u003cstrong\u003eNeed for occlusal therapy and prosthodontic treatment in the management of temporomandibular disorders. Part I. Occlusal interferences and occlusal adjustment\u003c/strong\u003e. \u003cem\u003eJ Oral Rehabil\u0026nbsp;\u003c/em\u003e2000, \u003cstrong\u003e27\u003c/strong\u003e(5):367-379.\u003c/li\u003e\n \u003cli\u003eMichelotti A, Iodice G: \u003cstrong\u003eThe role of orthodontics in temporomandibular disorders\u003c/strong\u003e. \u003cem\u003eJ Oral Rehabil\u0026nbsp;\u003c/em\u003e2010, \u003cstrong\u003e37\u003c/strong\u003e(6):411-429.\u003c/li\u003e\n \u003cli\u003eRoth RH, Rolfs DA: \u003cstrong\u003eFunctional occlusion for the orthodontist. Part II\u003c/strong\u003e. \u003cem\u003eJ Clin Orthod\u0026nbsp;\u003c/em\u003e1981, \u003cstrong\u003e15\u003c/strong\u003e(2):100-123.\u003c/li\u003e\n \u003cli\u003eRoth RH: \u003cstrong\u003eOcclusion and condylar position\u003c/strong\u003e. \u003cem\u003eAm J Orthod Dentofacial Orthop\u0026nbsp;\u003c/em\u003e1995, \u003cstrong\u003e107\u003c/strong\u003e(3):315-318.\u003c/li\u003e\n \u003cli\u003eOkeson JP: \u003cstrong\u003eManagement of temporomandibular disorders and occlusion.\u003c/strong\u003e, 7th edn: St. Louis: Elsevier Medicine; 2013.\u003c/li\u003e\n \u003cli\u003eKhan MT, Verma SK, Maheshwari S, Zahid SN, Chaudhary PK: \u003cstrong\u003eNeuromuscular dentistry: Occlusal diseases and posture\u003c/strong\u003e. \u003cem\u003eJ Oral Biol Craniofac Res\u0026nbsp;\u003c/em\u003e2013, \u003cstrong\u003e3\u003c/strong\u003e(3):146-150.\u003c/li\u003e\n \u003cli\u003eCorte-Real A, Abreu J, Figueiredo JP, Nunes T: \u003cstrong\u003eTemporomandibular trauma and reflections on personal evaluation\u003c/strong\u003e. \u003cem\u003eForensic Sci Med Pathol\u0026nbsp;\u003c/em\u003e2023.\u003c/li\u003e\n \u003cli\u003eDawson PE: \u003cstrong\u003eFunctional Occulsion from TMJ to Smile Design\u003c/strong\u003e. \u003cem\u003eJ Oral Health Journal\u0026nbsp;\u003c/em\u003e2007.\u003c/li\u003e\n \u003cli\u003eFricton JR, Schiffman EL: \u003cstrong\u003eReliability of a craniomandibular index\u003c/strong\u003e. \u003cem\u003eJ Dent Res\u0026nbsp;\u003c/em\u003e1986, \u003cstrong\u003e65\u003c/strong\u003e(11):1359-1364.\u003c/li\u003e\n \u003cli\u003eDerogatis L: \u003cstrong\u003eSCL-90-R: Administration, scoring and procedures manual for the Revised version.\u003c/strong\u003e; 1977.\u003c/li\u003e\n \u003cli\u003eFricton JR, Schiffman EL: \u003cstrong\u003eThe craniomandibular index: validity\u003c/strong\u003e. \u003cem\u003eJ Prosthet Dent\u0026nbsp;\u003c/em\u003e1987, \u003cstrong\u003e58\u003c/strong\u003e(2):222-228.\u003c/li\u003e\n \u003cli\u003eKamelchuk LS, Grace MG, Major PW: \u003cstrong\u003ePost-imaging temporomandibular joint space analysis\u003c/strong\u003e. \u003cem\u003eCranio\u0026nbsp;\u003c/em\u003e1996, \u003cstrong\u003e14\u003c/strong\u003e(1):23-29.\u003c/li\u003e\n \u003cli\u003eIkeda K, Kawamura A, Ikeda R: \u003cstrong\u003eAssessment of optimal condylar position in the coronal and axial planes with limited cone-beam computed tomography\u003c/strong\u003e. \u003cem\u003eJ Prosthodont\u0026nbsp;\u003c/em\u003e2011, \u003cstrong\u003e20\u003c/strong\u003e(6):432-438.\u003c/li\u003e\n \u003cli\u003eZhang P, Ge Y, Zhang J, Xu W: \u003cstrong\u003eOrthodontic treatment improves magnetic resonance imaging features and quality of life in adult patients with temporomandibular disorders\u003c/strong\u003e. \u003cem\u003eAm J Transl Res\u0026nbsp;\u003c/em\u003e2023, \u003cstrong\u003e15\u003c/strong\u003e(5):3723-3730.\u003c/li\u003e\n \u003cli\u003eKuttila M, Le Bell Y, Savolainen-Niemi E, Kuttila S, Alanen P: \u003cstrong\u003eEfficiency of occlusal appliance therapy in secondary otalgia and temporomandibular disorders\u003c/strong\u003e. \u003cem\u003eActa Odontol Scand\u0026nbsp;\u003c/em\u003e2002, \u003cstrong\u003e60\u003c/strong\u003e(4):248-254.\u003c/li\u003e\n \u003cli\u003eGavish A, Winocur E, Ventura YS, Halachmi M, Gazit E: \u003cstrong\u003eEffect of stabilization splint therapy on pain during chewing in patients suffering from myofascial pain\u003c/strong\u003e. \u003cem\u003eJ Oral Rehabil\u0026nbsp;\u003c/em\u003e2002, \u003cstrong\u003e29\u003c/strong\u003e(12):1181-1186.\u003c/li\u003e\n \u003cli\u003eLeite WB, Oliveira ML, Ferreira IC, Anjos CF, Barbosa MA, Barbosa AC: \u003cstrong\u003eEffects of 4-Week Diacutaneous Fibrolysis on Myalgia, Mouth Opening, and Level of Functional Severity in Women With Temporomandibular Disorders: A Randomized Controlled Trial\u003c/strong\u003e. \u003cem\u003eJ Manipulative Physiol Ther\u0026nbsp;\u003c/em\u003e2020, \u003cstrong\u003e43\u003c/strong\u003e(8):806-815.\u003c/li\u003e\n \u003cli\u003eBrooks SL, Brand JW, Gibbs SJ, Hollender L, Lurie AG, Omnell KA, Westesson PL, White SC: \u003cstrong\u003eImaging of the temporomandibular joint: a position paper of the American Academy of Oral and Maxillofacial Radiology\u003c/strong\u003e. \u003cem\u003eOral Surg Oral Med Oral Pathol Oral Radiol Endod\u0026nbsp;\u003c/em\u003e1997, \u003cstrong\u003e83\u003c/strong\u003e(5):609-618.\u003c/li\u003e\n \u003cli\u003eWeinberg LA: \u003cstrong\u003eRole of condylar position in TMJ dysfunction-pain syndrome\u003c/strong\u003e. \u003cem\u003eJ Prosthet Dent\u0026nbsp;\u003c/em\u003e1979, \u003cstrong\u003e41\u003c/strong\u003e(6):636-643.\u003c/li\u003e\n \u003cli\u003eMajor PW, Kinniburgh RD, Nebbe B, Prasad NG, Glover KE: \u003cstrong\u003eTomographic assessment of temporomandibular joint osseous articular surface contour and spatial relationships associated with disc displacement and disc length\u003c/strong\u003e. \u003cem\u003eAm J Orthod Dentofacial Orthop\u0026nbsp;\u003c/em\u003e2002, \u003cstrong\u003e121\u003c/strong\u003e(2):152-161.\u003c/li\u003e\n \u003cli\u003eZhang ZL, Cheng JG, Li G, Zhang JZ, Zhang ZY, Ma XC: \u003cstrong\u003eMeasurement accuracy of temporomandibular joint space in Promax 3-dimensional cone-beam computerized tomography images\u003c/strong\u003e. \u003cem\u003eOral Surg Oral Med Oral Pathol Oral Radiol\u0026nbsp;\u003c/em\u003e2012, \u003cstrong\u003e114\u003c/strong\u003e(1):112-117.\u003c/li\u003e\n \u003cli\u003eMongini F: \u003cstrong\u003eAbnormalities in condylar and positions.in:Silberg,Clark GT,editers.Abnormal jaw mechanics,diagnosis and treatment.\u003c/strong\u003e In: \u003cem\u003eChicago:Quintessence,.\u003c/em\u003e vol. 30; 1980.\u003c/li\u003e\n \u003cli\u003eWestesson PL, Kurita K, Eriksson L, Katzberg RW: \u003cstrong\u003eCryosectional observations of functional anatomy of the temporomandibular joint\u003c/strong\u003e. \u003cem\u003eOral Surg Oral Med Oral Pathol\u0026nbsp;\u003c/em\u003e1989, \u003cstrong\u003e68\u003c/strong\u003e(3):247-251.\u003c/li\u003e\n \u003cli\u003eSahler LG, Morris TW, Katzberg RW, Tallents RH: \u003cstrong\u003eMicroangiography of the rabbit temporomandibular joint in the open and closed jaw positions\u003c/strong\u003e. \u003cem\u003eJ Oral Maxillofac Surg\u0026nbsp;\u003c/em\u003e1990, \u003cstrong\u003e48\u003c/strong\u003e(8):831-834.\u003c/li\u003e\n \u003cli\u003eWitkowska A: \u003cstrong\u003eAn outline of the history of electromyography. The significance of surface electromyography in neurophysiological diagnosis.\u0026nbsp;\u003c/strong\u003e. \u003cem\u003eNowiny Lekarskie\u0026nbsp;\u003c/em\u003e2008, \u003cstrong\u003e77\u003c/strong\u003e(3):227-230.\u003c/li\u003e\n \u003cli\u003eWozniak K, Piatkowska D, Lipski M, Mehr K: \u003cstrong\u003eSurface electromyography in orthodontics - a literature review\u003c/strong\u003e. \u003cem\u003eMed Sci Monit\u0026nbsp;\u003c/em\u003e2013, \u003cstrong\u003e19\u003c/strong\u003e:416-423.\u003c/li\u003e\n \u003cli\u003eVisser A, McCarroll RS, Naeije M: \u003cstrong\u003eMasticatory muscle activity in different jaw relations during submaximal clenching efforts\u003c/strong\u003e. \u003cem\u003eJ Dent Res\u0026nbsp;\u003c/em\u003e1992, \u003cstrong\u003e71\u003c/strong\u003e(2):372-379.\u003c/li\u003e\n \u003cli\u003eScopel V, Alves da Costa GS, Urias D: \u003cstrong\u003eAn electromyographic study of masseter and anterior temporalis muscles in extra-articular myogenous TMJ pain patients compared to an asymptomatic and normal population\u003c/strong\u003e. \u003cem\u003eCranio\u0026nbsp;\u003c/em\u003e2005, \u003cstrong\u003e23\u003c/strong\u003e(3):194-203.\u003c/li\u003e\n \u003cli\u003ePinho JC, Caldas FM, Mora MJ, Santana-Penin U: \u003cstrong\u003eElectromyographic activity in patients with temporomandibular disorders\u003c/strong\u003e. \u003cem\u003eJ Oral Rehabil\u0026nbsp;\u003c/em\u003e2000, \u003cstrong\u003e27\u003c/strong\u003e(11):985-990.\u003c/li\u003e\n \u003cli\u003eTartaglia GM, Moreira Rodrigues da Silva MA, Bottini S, Sforza C, Ferrario VF: \u003cstrong\u003eMasticatory muscle activity during maximum voluntary clench in different research diagnostic criteria for temporomandibular disorders (RDC/TMD) groups\u003c/strong\u003e. \u003cem\u003eMan Ther\u0026nbsp;\u003c/em\u003e2008, \u003cstrong\u003e13\u003c/strong\u003e(5):434-440.\u003c/li\u003e\n \u003cli\u003eFerrario VF, Sforza C: \u003cstrong\u003eBiomechanical model of the human mandible in unilateral clench: distribution of temporomandibular joint reaction forces between working and balancing sides\u003c/strong\u003e. \u003cem\u003eJ Prosthet Dent\u0026nbsp;\u003c/em\u003e1994, \u003cstrong\u003e72\u003c/strong\u003e(2):169-176.\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":"bmc-oral-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ohea","sideBox":"Learn more about [BMC Oral Health](http://bmcoralhealth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ohea/default.aspx","title":"BMC Oral Health","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Temporomandibular Joint Disorders, Stabilization Splint, Surface Electromyogram, Individual Musculoskeletally Stable Position","lastPublishedDoi":"10.21203/rs.3.rs-4582957/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4582957/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjective\u003c/strong\u003e: TMD (Temporomandibular Joint Disorders) is the dysfunction of group of muscles and bones in the joint area, the main symptom of TMD is the pain of the chewing muscles and (or) the temporomandibular joints, which seriously affects the life qualities of patients and even social behaviors. Stabilization splint is one of the commonly used effective reversible treatment, the determination of the jaw position is the critical point in the process of treatment.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e In this study, we firstly used Fricton Index to evaluate the clinical curative effect of TMD with the treatment of IMS (Individual MusculoskeletallyStable) position stabilization splint; then CBCT (Cone Beam Computerized Tomography) was used to observe the TMJ condylar position changes of TMD before and after the treatment of IMS stabilization splint; finally sEMG (surface-Electromyogram) was used to observe the changes of electromyography of AT (anterior temporalis) and MM (masseter muscle) of TMD before and after the treatment of IMS stabilization splint.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults and conclusions:\u003c/strong\u003e IMS stabilization splint is one of efficient reversible treatments for TMD, which can relieve and even eliminate the TMD symptoms, especially for ease of pain and corrective to jaw movement disorder; After the treatment of IMS, posterior space of TMJ has the tendency of increasing; IMS stabilization splint may ease even cure the TMD by removing the masticatory muscle disorders, terminating the masticatory muscles antagonism between bad function so as to make them function in harmony with each other.\u003c/p\u003e","manuscriptTitle":"The preliminary study of the effects of individual musculoskeletally stable position in the treatment of temporomandibular disorders","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-07-16 22:09:49","doi":"10.21203/rs.3.rs-4582957/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-07-10T04:40:30+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-07-07T16:15:32+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-07-02T05:33:06+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"144973913809372351928492025058280436606","date":"2024-06-28T08:27:03+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"94738533707804616352592933738101808778","date":"2024-06-23T12:56:14+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"90471417229723752099223428760003249967","date":"2024-06-21T19:20:29+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"68702283220824262291589189953935904539","date":"2024-06-21T16:59:15+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-06-21T16:56:44+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2024-06-19T12:34:35+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-06-18T11:40:32+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-06-18T11:38:59+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Oral Health","date":"2024-06-14T15:13:43+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-oral-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ohea","sideBox":"Learn more about [BMC Oral Health](http://bmcoralhealth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ohea/default.aspx","title":"BMC Oral Health","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"fa156800-7d46-422f-922b-bbefdf400ac2","owner":[],"postedDate":"July 16th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-09-16T16:04:38+00:00","versionOfRecord":{"articleIdentity":"rs-4582957","link":"https://doi.org/10.1186/s12903-024-04864-9","journal":{"identity":"bmc-oral-health","isVorOnly":false,"title":"BMC Oral Health"},"publishedOn":"2024-09-13 15:57:59","publishedOnDateReadable":"September 13th, 2024"},"versionCreatedAt":"2024-07-16 22:09:49","video":"","vorDoi":"10.1186/s12903-024-04864-9","vorDoiUrl":"https://doi.org/10.1186/s12903-024-04864-9","workflowStages":[]},"version":"v1","identity":"rs-4582957","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4582957","identity":"rs-4582957","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}