Analysis of the dimensional changes in bone grafts after maxillary sinus augmentation procedure.

Analysis of the dimensional changes in bone grafts after maxillary sinus augmentation procedure. | 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 Analysis of the dimensional changes in bone grafts after maxillary sinus augmentation procedure. Michael Saminsky, Dor Peretz, Gil Slutzkey, Perry Raz, Ilan Beitlitum This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4816739/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Purpose During sinus augmentation, various bone graft substitutes and/or their combination are used. They have varying rates of remodeling and cause different volume changes in the grafted material. This study aimed to investigate the potential time-dependent dimensional changes in graft materials of xenografts and allografts placed using the layering technique, (xenograft placed close to the sinus membrane, while the bone allograft fills the remaining sinus cavity) following a maxillary sinus elevation procedure. Methods CBCT records were available for 16 patients referred for contralateral sinus augmentation and implant placement. In these cases, additional CBCT performed prior to the procedure revealed graft dimensional changes. Linear measurements of the augmented bone grafts were performed at three identical locations at two-time points. Linear regression, one-way ANOVA and Pearson's and Spearman’s correlations were used for statistical analysis. P values ≤ 0.05 were considered statistically significant. Results There was no statistically significant variation in the rate of dimensional change across the different evaluated locations in the augmented graft (p = 0.816). At the peak of augmentation, each additional month corresponded to a decrease of 1.556 mm 2 (95% CI, -2.723 to -0.388) in the bone dimensions. The changes of the amount of bone filler material above the implant was related to gender (t= -2.167, p = 0.049) and implant diameter (t = 3.251, p = 0.012). Conclusions The combination of xenografts and allografts in maxillary sinus augmentation, applying layer technique, underwent dimensional changes over time and amounted to a 1.5mm 2 reduction per month. More residual bone was observed among female patients and wider implant diameters. sinus augmentation bone graft CBCT analysis Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 BACKGROUND Loss of posterior maxillary teeth often leads to bone resorption and increased pneumatization of the maxillary sinus. 1 The edentulous area may exhibit severe bone atrophy that can compromise the placement of dental implants at this site. 2 In such cases, bone augmentation is required prior to dental implantation. A study examining the dimensional changes of the sinus after tooth loss found that maxillary sinus pneumatization occurs more significantly in the area where the second pre-molar is missing. 3 Furthermore, it was noted that pneumatization in the region of the first missing molar indicates a greater requirement for pre-implant bone augmentation. 4 Sinus floor augmentation was first introduced by Tatum in 1976 during his presentation and published for the first time in 1980 by Boyne and James. 5 The surgical procedure has undergone significant development and changes, and currently, sinus floor elevation is a widely accepted method to increase bone volume before dental implant placement. 6 The procedure is designed to increase the bone volume in the vertical dimension of the maxillary bone. Its objective is to counteract bone loss caused by sinus pneumatization and facilitate the placement of dental implants that are longer than the height of the original bone. 7 During the surgery, the clinician gently lifts the maxillary sinus membrane, creating space between the membrane and the sinus floor. This space is typically filled with a graft material that will promote bone regeneration and allow the placement of an implant that will be integrated fully into the new bone. Depending on the dimensions of the pristine bone, the clinician will decide whether to perform a simultaneous procedure, which involves the immediate placement of the implant, or a delayed placement of the implant. During sinus augmentation, a variety of bone graft substitutes are utilized, such as autogenous bone (bone taken from the patient's body or the implantation site), allogeneic bone (bone from a different human donor), xenogenic bone (bone from an animal source), and alloplastic materials (synthetic bone substitutes). A blend of these materials may also be employed. 8 Different types of bone grafts have varying rates of bone remodeling and lead to different volume changes in the grafted bone within the maxillary sinus. The volume of the implanted bone filler material is better maintained when a xenograft is added. The ratio of the xenograft to autogenous bone significantly affects the changes in volume. 9 Research conducted to evaluate bone remodeling rates with various bone graft materials for treating maxillary defects revealed that autogenous bone had the fastest bone integration. 10 Furthermore, the use of xenograft resulted in more effective bone synthesis and remodeling than an allograft. In comparison, synthetic bone graft substitutes performed poorly compared to the other materials discussed. 11 , 12 The combination of xenografts and allografts in maxillary sinus elevation procedures has become a common approach. Allografts provide an osteoconductive scaffold for bone regeneration, while xenografts contribute to graft volume and stability as they are slowly resorbed. This results in successful bone regeneration in the maxillary sinus. 17 – 19 The bone graft can significantly adapt shape and volume due to renewed maxillary sinus pneumatization. It is crucial to accurately assess the dimensional changes of the transplanted bone as it greatly impacts the success of the treatment. Loss of height and width of the bone graft can have a significant effect on the long-term success of the dental implant. Various studies have used cone-beam computed tomography (CBCT) scans to measure these changes. In one study, 13 26 CBCT scans of 13 patients showed an increase in bone graft volume of approximately 9% eight months after surgery, while another study of 32 CBCT scans from 16 patients reported a decrease in volume of approximately 26% six months post-surgery. 14 Despite differences in surgical techniques and graft materials, most studies indicate a post-surgery reduction in bone graft volume. 15 Manual segmentation of the sinus floor and graft material in CBCT scans is employed as a method for these assessments, such as in a study that revealed a 25% average decrease in the volumetric dimensions of the bone graft across 20 patients. 16 The present study aimed to investigate the potential dimensional changes in graft materials several months after the maxillary sinus elevation procedure. The study aims to assess any changes in the dimensions of grafts over time in individuals who have undergone the maxillary sinus elevation procedure using a combination of xenografts and allografts in the layering technique. Understanding the long-term stability and behavior of graft materials used in oral and maxillofacial surgery is crucial. By determining the extent of dimensional changes that occur in these grafts, we aim to gain valuable insights into their performance and improve patient outcomes. This research will contribute to our understanding of graft behavior and provide important information on the long-term success of this surgical procedure. METHODS This retrospective, cohort study was based on CBCT scans extracted from dental records of patients in the University School of Dental Medicine, which were selected based on their alignment with the predetermined inclusion and exclusion criteria, from 01\2009 to 12\2020. All treatments were performed by 2 experienced periodontists (I.B., G.S.). The study protocol was approved by the Institution Ethics Committee in accordance with Declaration of Helsinki (confirmation no. 003479-1). Patients included in the study were older than 18 years, underwent LMSA between 01\2009 and 12\2020. The procedures were performed only after ensuring there is no active periodontal disease. Only patients who required implant placement on the contralateral side and underwent a third CBCT scan were included. Contraindications to the surgery such as history of head and neck cancer and/or radiotherapy, immune deficiency, and immuno-suppressant medications intake and lack of third (follow-up) CBCT scan served as exclusion criteria for the study. All patients signed an informed consent before treatment. Surgery was performed under local anesthesia according to the technique described by Boyne and James. 5 A full-thickness access flap was prepared with midcrestal and vertical releasing incisions. A lateral window was created using a low-speed headpiece cooled by sterile physiologic saline. The access window was extended laterally and apically, the sinus membrane was raised, and a particulate bone graft was placed underneath. A combination of approximately 0.5 g deproteinized bovine bone mineral (DBBM), (Bio-Oss, Geistlich) and 2 mL small particulate (250µ-1000µ), cortico-cancellous mineralized bone allograft (Maxgraft, Botiss) was applied using a bilayer technique. DBBM was placed close to the sinus membrane, while the particulate mineralized bone allograft filled the remaining sinus cavity. The access window was covered with resorbable collage membrane (OsseoGuard, Zimmer Biomet Dental) (Fig. 1 A-D). A periosteal incision was made, and the soft tissues were approximated and sutured with horizontal mattress and single interrupted sutures. Postoperative instructions included rinsing with 0.2% chlorhexidine solution twice daily for 2 weeks, and antibiotics were prescribed for 10 days (Augmentin 875 mg BID, GlaxoSmithKline). Patients who were allergic to penicillin received Dalacin-C 150 mg qid (Pfizer). Analgesics were provided only when needed. Demographic data, including age, gender, and smoking status, were extracted from the patient’s records. Each patient underwent three CBCT scans: the first scan (T0) was performed before LMSA to assess the existing bone level and the anatomical limitations, the second scan (T1) was performed at least five months after LMSA to evaluate the bone level before implant placement, and the third scan (T2) was performed after implant placement and rehabilitation. This was not conducted specifically for the examined site. Instead, it was performed with the aim of facilitating future implant placement on the opposite side. All CBCT scans of the patients were performed between 2009 and 2022 at the Maxillofacial Imaging Institute at the School of Dental Medicine. The examined sites in all patients were exposed to radiation doses of 69–80 µSv for a single CBCT scan. From the patients' CBCT scans, linear bone implant measurements were performed at three identical locations for each time point. The first location was the point with the highest augmentation (peak of augmentation), the second location was 4 mm mesial to the peak of augmentation, and the third location was 4 mm distal to the peak of augmentation. The measurement was performed by manually marking the area and calculating the surface area using ImageJ software (US National Institute of Health). Furthermore, the distance from the apex of the dental implant to the peak of augmentation was measured for each patient in the T2 scans (Fig. 2 ). Linear regression was used to ascertain the effects of multiple variables on a continuous dependent variable. Possible confounders were added to the regression model to neutralize their effect. One-way ANOVA with post-hoc tests and Bonferroni correction for multiple tests was used to test for differences between groups' means. The Kolmogorov-Smirnov normality test was used to test if a variable follows a normal distribution. Student's t-test was used to test for a difference between the means of two groups on a normal continuous dependent variable. Paired t-test was used when the observations were paired. Pearson's correlation was used to determine the strength and direction of a linear relationship between two continuous normally distributed variables. Spearman's correlation was used to determine the strength and direction of a relationship between two continuous non-normally distributed variables. P-values were corrected for multiple tests using the Benjamini-Hochberg (BH) method. Descriptive statistics and statistical analysis were done using SPSS 28 software for Windows (IBM). Power calculation for minimal required study cohort was done using G*Power 3.1.9.4. 20 We assumed that the correlation between the time between T1 and T2 and the delta between T2 and T1 at the peak augmentation would be 0.6. Then for a one-sided Pearson correlation test, a test significance 0.05 and power 0.8, we would need a sample of 15 patients. RESULTS A total of 16 patients (12 females and 4 males) were found eligible for the study. (Fig. 3 ) Those availed 48 CBCT scans for the analysis. The mean patient’s age was 66 years (52–79 years, SD = 7.946). Among the participants, 2 individuals reported being smokers, with both smoking up to 10 cigarettes a day. All subjects were otherwise healthy. The mean time elapsed between T1 and T2 was 18 months (4–46 months, SD = 12.463). A total of 34 implants were placed, from three distinct types: MIS SEVEN [MIS implant technologies Ltd] (20 implants, 58.8%), LANCE [MIS implant technologies Ltd] (8 implants, 23.5%) and ZIMMER [Zimmer Biomet Dental] (6 implants, 17.7%). Most participants (63%) received implants with a diameter of 3.75mm. Additionally, 36% of participants received implants in the 4.1-4.2mm diameter range (Table 1 ). Table 1 – Implant distribution according to position, size, and type Patient No. Position Length [mm] Diameter [mm] Type 1 #24 11.5 3.75 MIS SEVEN #25 11.5 3.75 MIS SEVEN #26 11.5 3.75 MIS SEVEN 2 #16 11.5 3.75 MIS SEVEN 3 #16 13 3.75 LANCE #17 13 3.75 LANCE 4 #24 13 3.75 MIS SEVEN #25 13 3.75 MIS SEVEN #26 11.5 3.75 MIS SEVEN 5 #26 13 3.75 MIS SEVEN 6 #16 13 3.75 MIS SEVEN #17 13 3.75 MIS SEVEN 7 #14 13 3.75 MIS SEVEN #15 13 3.75 MIS SEVEN #16 13 4.2 MIS SEVEN 8 #16 13 4.2 MIS SEVEN 9 #25 13.5 4.1 ZIMMER #26 11.5 4.2 ZIMMER 10 #26 11.5 4.1 ZIMMER #27 11.5 4.1 ZIMMER 11 #14 13 3.75 MIS SEVEN #15 11.5 3.75 MIS SEVEN #16 11.5 3.75 MIS SEVEN 12 #26 13 4.2 LANCE #27 13 4.2 LANCE 13 #25 8 4.2 LANCE #26 10 4.2 LANCE #27 11.5 4.2 LANCE 14 #15 11.5 3.75 MIS SEVEN #16 13 3.75 MIS SEVEN #17 11.5 4.2 MIS SEVEN 15 #16 11.5 3.7 ZIMMER #17 11.5 4.1 ZIMMER 16 #16 11.5 4.2 LANCE Between T1 and T2, changes in the bone dimensions at the examined site were observed. At the peak of augmentation, there was a mean change of -30.89mm 2 (SD = 29.751). At a 4mm distal to the peak and at 4mm mesial to the peak the mean volume changes of -26.25mm 2 (SD = 32.384) and − 27.71mm 2 (SD = 28.295) respectively were observed. (Fig. 3 ) Based on the results of the repeated-measures Analysis of Variance (ANOVA), there was no statistically significant variation in dimensional change across the evaluated locations (p = 0.816) (Fig. 4 ). At the peak of augmentation, the time interval between T1 and T2 had a statistically significant predictive correlation with the bone dimensions change (t = -2.931, p = 0.027). Each additional month between T1 and T2 corresponded to a decrease of 1.556 mm 2 (95% CI, -2.723 to -0.388) in the bone dimensions. The mean height of augmentation measured above the implant at the peak of augmentation was 4.86mm (2.04-7.91mm). A regression analysis yielded that augmentation height above the implant is related to gender (t= -2.167, p = 0.049) and implant diameter (t = 3.251, p = 0.012). DISCUSSION This study aimed to investigate dimensional changes in graft materials after maxillary sinus elevation procedures using layers of xenograft and allograft bone filler materials. These materials were arranged in two layers. The radiopaque appearance of xenogeneic bone substitute enables clear demarcation of the graft borderline and its relation to the Schneiderian membrane (Fig. 5 ). The results showed a consistent trend of decreasing bone dimensions over time, with a statistically significant reduction between the T1 and T2 scans. This suggests that clinicians and researchers should be aware of these changes and emphasize the need for long-term monitoring to achieve the best outcomes. The average decrease in bone dimensions around the peak of augmentation is consistent with previous studies that have reported a reduction in bone graft volume over time. 14 , 15 . The findings indicate that despite improvements in graft materials and surgical techniques, the post-operative shrinkage of grafts continues to be a challenge. Furthermore, our results support the idea that time plays a significant role in graft resorption. Specifically, for every additional month between T1 and T2, there was a reduction of 1.556 mm 2 in bone dimensions. The findings of the study are consistent with other studies that also reported a decrease in graft volume following maxillary sinus elevation procedure. 13 , 14 The choice of graft material has been a focal point in the scientific community, and this study provides further insights into the advantages and disadvantages of xenografts and allografts. Allografts provide an osteoconductive scaffold, and xenografts contribute to graft volume and stability. Both seem susceptible to the general trend of graft resorption and shrinkage. 15 Based on previous publications, it could be assumed that creating a xenograft outer layer may reduce bone volumetric loss. 21 Yet, a randomized control study comparing graft volume reduction with other materials could clarify the potential contribution of xenograft to dimensional stability. Over time, the observed trend toward dimensional reduction suggests that clinicians must carefully consider the timing between the maxillary sinus elevation procedure and the subsequent implant placement. Although the xenograft remained stable over time, using this combination in the layering technique did not prevent a volumetric change in the height of bone in the sinus over time. The influence of gender and implant diameter on augmentation height above the implant is a novel finding. However, drawing definitive conclusions from this study is challenging due to most participants being women. The selection of implant diameter is influenced by bone dimensions and patient-specific treatment planning. The study primarily relied on two-dimensional measurements, which, while informative, are inherently limited in accuracy compared to three-dimensional assessments. To achieve a more comprehensive and precise understanding of graft material volume changes, three-dimensional measurements are required. Such an approach will provide critical insights into the complexities of graft resorption and bone dimensional changes. The analyzed CBCTs present a relatively broad span of follow-up times (4–46 months, mean 18 months). This variability in timeframe is a result of the treatment plan required for the contralateral sinus. The mean height of augmentation measured above the implant at the peak of augmentation was 4.86mm. Evaluating the remaining bone above the implants in T2 is important in order to demonstrate that no membrane perforation occurred during implant placement, which could have led to the bone volume collapse over time. This study’s limitations include a relatively small sample size of 16 patients and a diverse range of time between T1 and T2 scans. Two experienced periodontists conducted all procedures, which may not be applicable to all clinicians. Future research should strive to include a larger and more diverse group. Moreover, differentiation between the allograft and the pristine patient bone may not always be straightforward, particularly several months following the surgical procedure. CONCLUSIONS The present study offers valuable insights into the long-term behavior of graft materials used in maxillary sinus elevation procedures. While the combination of xenografts and allografts presents clinical advantages, our findings highlight the necessity of ongoing monitoring and consideration of time elapsed between procedures to ensure optimal outcomes. The relationship between implant diameter, gender, and graft resorption coupled with the potential enhancement in accuracy through three-dimensional measurements, also delineates new avenues for future research. Abbreviations CBCT cone beam computer tomography LMSA lateral maxillary sinus augmentation qid four times a day Declarations Author contributions Conceptualization: I.B., G.S; project administration: D.P and M.S; data curation: P.R; validation: D.P, P.R, G.S; investigation: D.P; formal analysis: D.P. and M.S. analyzed the data; writing – original draft: M.S, I.B. led the writing; writing – review & editing: all authors contributed to the writing and editing. Funding The authors declare that no funds, grants, or other support were received during the preparation of this manuscript. Data availability The authors confirm that there is no associated data included in this manuscript. Ethics approval The study protocol was approved by the Institution Ethics Committee (no. 003479-1). Consent to participate Written informed consent was obtained from the patients. Competing interests The authors have no relevant financial or non-financial interests to disclose. Declarations of interest: none. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request. References Umanjec-Korac S, Wu G, Hassan B, Liu Y, Wismeijer D. A retrospective analysis of the resorption rate of deproteinized bovine bone as maxillary sinus graft material on cone beam computed tomography. 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Volumetric changes of grafted volumes and the Schneiderian membrane after transcrestal and lateral sinus floor elevation procedures: A clinical, pilot study. J Clin Periodontol. 2017;44:660–71. Klijn RJ, van den Beucken JJ, Bronkhorst EM, Berge SJ, Meijer GJ, Jansen JA. Predictive value of ridge dimensions on autologous bone graft resorption in staged maxillary sinus augmentation surgery using Cone-Beam CT. Clin Oral Implants Res. 2012;23:409–15. Block MS, Ducote CW, Mercante DE. Horizontal augmentation of thin maxillary ridge with bovine particulate xenograft is stable during 500 days of follow-up: preliminary results of 12 consecutive patients. J Oral Maxillofac Surg. 2012;70:1321–30. Buser D, Dula K, Hirt HP, Schenk RK. Lateral ridge augmentation using autografts and barrier membranes: a clinical study with 40 partially edentulous patients. J Oral Maxillofac Surg. 1996;54:420–32. discussion 432-3. von Arx T, Buser D. Horizontal ridge augmentation using autogenous block grafts and the guided bone regeneration technique with collagen membranes: a clinical study with 42 patients. Clin Oral Implants Res. 2006;17:359–66. Faul F, Erdfelder E, Buchner A, Lang AG. Statistical power analyses using G*Power 3.1: tests for correlation and regression analyses. Behav Res Methods. 2009;41:1149–60. Cordaro L, Torsello F, Morcavallo S, di Torresanto VM. Effect of bovine bone and collagen membranes on healing of mandibular bone blocks: a prospective randomized controlled study. Clin Oral Implants Res. 2011;22:1145–50. Additional Declarations No competing interests reported. Supplementary Files STROBEStatement.docx Cite Share Download PDF Status: Posted Version 1 posted 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. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4816739","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":345028599,"identity":"454c9e2f-ae6d-4b58-9474-dab14cae454a","order_by":0,"name":"Michael Saminsky","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA3ElEQVRIiWNgGAWjYHACNhDBI8HMfABIS8iQooUtAaSFh2gtDBIMPAZgvQTVy7cffvbg455tMpLtPJ9f3aix4GFgP3x0Az4tBmfSzA1nPLvNI83Mu8065xjQYTxpaTfwamHIYZPmOXCbRw6oxTiHDahFgscMrxb5/jds0n/AWnieGef8I0ILww2gLQwHQA7jYX6c20aEFoMbz8wke4BaJJvZzJhz+yR42Aj5Rb4/+ZnEjwO37SXOH378OedbnRw/++Fj+B2GBNgkwCSxykGA+QMpqkfBKBgFo2DkAACurkDGsLvKBQAAAABJRU5ErkJggg==","orcid":"","institution":"Tel Aviv University","correspondingAuthor":true,"prefix":"","firstName":"Michael","middleName":"","lastName":"Saminsky","suffix":""},{"id":345028602,"identity":"933a5e98-401b-42b5-8712-9106756e4bd8","order_by":1,"name":"Dor Peretz","email":"","orcid":"","institution":"Tel Aviv University","correspondingAuthor":false,"prefix":"","firstName":"Dor","middleName":"","lastName":"Peretz","suffix":""},{"id":345028603,"identity":"3dcf441c-8c2e-42e9-8d92-0291485b8757","order_by":2,"name":"Gil Slutzkey","email":"","orcid":"","institution":"Tel Aviv University","correspondingAuthor":false,"prefix":"","firstName":"Gil","middleName":"","lastName":"Slutzkey","suffix":""},{"id":345028605,"identity":"6fb8523c-28e8-455a-9c7a-c16b4f55fbef","order_by":3,"name":"Perry Raz","email":"","orcid":"","institution":"Tel Aviv University","correspondingAuthor":false,"prefix":"","firstName":"Perry","middleName":"","lastName":"Raz","suffix":""},{"id":345028611,"identity":"1985653b-a26a-4158-8c64-142b161b90b9","order_by":4,"name":"Ilan Beitlitum","email":"","orcid":"","institution":"Tel Aviv University","correspondingAuthor":false,"prefix":"","firstName":"Ilan","middleName":"","lastName":"Beitlitum","suffix":""}],"badges":[],"createdAt":"2024-07-28 12:54:31","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4816739/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4816739/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":64008527,"identity":"5dcee60b-75a1-42b8-a3d8-acb49a607d99","added_by":"auto","created_at":"2024-09-04 23:03:22","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":2174358,"visible":true,"origin":"","legend":"\u003cp\u003e(A-D) – A bilayer technique in maxillary sinus augmentation.\u003c/p\u003e\n\u003cp\u003eA - The lateral window with sinus membrane was raised.\u003c/p\u003e\n\u003cp\u003eB - DBBM was placed close to the sinus membrane as a first layer.\u003c/p\u003e\n\u003cp\u003eC - The particulate mineralized bone allograft filled the remaining sinus cavity.\u003c/p\u003e\n\u003cp\u003eD - The access window covered with resorbable collage membrane.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-4816739/v1/600cc9847df75efe9b3ffa9c.png"},{"id":64008174,"identity":"87018e49-3e28-42f4-b7d4-9ee06cda8439","added_by":"auto","created_at":"2024-09-04 22:55:22","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":295143,"visible":true,"origin":"","legend":"\u003cp\u003eAugmented bone change measurement. Residual bone graft height measured apical to the implant (yellow line).\u003c/p\u003e","description":"","filename":"Fig.2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4816739/v1/eeb91eb74dc29384a21ed048.jpg"},{"id":64008170,"identity":"ceb0e85a-ea63-4f57-accd-18a25af703a5","added_by":"auto","created_at":"2024-09-04 22:55:22","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":167296,"visible":true,"origin":"","legend":"\u003cp\u003eConsort flow diagram\u003c/p\u003e","description":"","filename":"Fig.3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4816739/v1/5375011dcb088c684ebe331d.jpg"},{"id":64008175,"identity":"c7ca9cfc-974a-4fde-aded-0cde1c5f0ec8","added_by":"auto","created_at":"2024-09-04 22:55:22","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":97690,"visible":true,"origin":"","legend":"\u003cp\u003eMean Bone Area Changes measured between T2-T1 in three locations (Peak, Mesial, Distal). Error bars: 95% CI\u003c/p\u003e","description":"","filename":"Fig.4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4816739/v1/35dafd0fad9461a355991c8f.jpg"},{"id":64008528,"identity":"a3c690e0-27e6-4163-bcfe-954e60ed095a","added_by":"auto","created_at":"2024-09-04 23:03:22","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":267873,"visible":true,"origin":"","legend":"\u003cp\u003eCBCT prior to implant placement. The purple area describes the augmented bone substitutes. Note the difference in color toning between upper (xenograft) and lower (allograft) compartments. The red area describes the pristine bone.\u003c/p\u003e","description":"","filename":"Fig.5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4816739/v1/aa7266ed682f9ec62634e4a7.jpg"},{"id":64883295,"identity":"6098c13b-99bf-4b02-b5a0-5c2f18c86613","added_by":"auto","created_at":"2024-09-20 04:01:05","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3340195,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4816739/v1/e955450d-68a9-472a-8cac-a631abd452c1.pdf"},{"id":64008172,"identity":"c35480fb-2c4f-4797-87bb-a1a3823b1381","added_by":"auto","created_at":"2024-09-04 22:55:22","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":22212,"visible":true,"origin":"","legend":"","description":"","filename":"STROBEStatement.docx","url":"https://assets-eu.researchsquare.com/files/rs-4816739/v1/b94353a7ac0a3e762dde1640.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Analysis of the dimensional changes in bone grafts after maxillary sinus augmentation procedure.","fulltext":[{"header":"BACKGROUND","content":"\u003cp\u003eLoss of posterior maxillary teeth often leads to bone resorption and increased pneumatization of the maxillary sinus.\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e The edentulous area may exhibit severe bone atrophy that can compromise the placement of dental implants at this site.\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e In such cases, bone augmentation is required prior to dental implantation. A study examining the dimensional changes of the sinus after tooth loss found that maxillary sinus pneumatization occurs more significantly in the area where the second pre-molar is missing.\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e Furthermore, it was noted that pneumatization in the region of the first missing molar indicates a greater requirement for pre-implant bone augmentation.\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eSinus floor augmentation was first introduced by Tatum in 1976 during his presentation and published for the first time in 1980 by Boyne and James. \u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e The surgical procedure has undergone significant development and changes, and currently, sinus floor elevation is a widely accepted method to increase bone volume before dental implant placement. \u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e The procedure is designed to increase the bone volume in the vertical dimension of the maxillary bone. Its objective is to counteract bone loss caused by sinus pneumatization and facilitate the placement of dental implants that are longer than the height of the original bone. \u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e During the surgery, the clinician gently lifts the maxillary sinus membrane, creating space between the membrane and the sinus floor. This space is typically filled with a graft material that will promote bone regeneration and allow the placement of an implant that will be integrated fully into the new bone. Depending on the dimensions of the pristine bone, the clinician will decide whether to perform a simultaneous procedure, which involves the immediate placement of the implant, or a delayed placement of the implant.\u003c/p\u003e \u003cp\u003eDuring sinus augmentation, a variety of bone graft substitutes are utilized, such as autogenous bone (bone taken from the patient's body or the implantation site), allogeneic bone (bone from a different human donor), xenogenic bone (bone from an animal source), and alloplastic materials (synthetic bone substitutes). A blend of these materials may also be employed.\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e Different types of bone grafts have varying rates of bone remodeling and lead to different volume changes in the grafted bone within the maxillary sinus. The volume of the implanted bone filler material is better maintained when a xenograft is added. The ratio of the xenograft to autogenous bone significantly affects the changes in volume.\u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e Research conducted to evaluate bone remodeling rates with various bone graft materials for treating maxillary defects revealed that autogenous bone had the fastest bone integration.\u003csup\u003e\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e Furthermore, the use of xenograft resulted in more effective bone synthesis and remodeling than an allograft. In comparison, synthetic bone graft substitutes performed poorly compared to the other materials discussed.\u003csup\u003e\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e,\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e The combination of xenografts and allografts in maxillary sinus elevation procedures has become a common approach. Allografts provide an osteoconductive scaffold for bone regeneration, while xenografts contribute to graft volume and stability as they are slowly resorbed. This results in successful bone regeneration in the maxillary sinus.\u003csup\u003e\u003cspan additionalcitationids=\"CR18\" citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eThe bone graft can significantly adapt shape and volume due to renewed maxillary sinus pneumatization. It is crucial to accurately assess the dimensional changes of the transplanted bone as it greatly impacts the success of the treatment. Loss of height and width of the bone graft can have a significant effect on the long-term success of the dental implant. Various studies have used cone-beam computed tomography (CBCT) scans to measure these changes. In one study,\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e 26 CBCT scans of 13 patients showed an increase in bone graft volume of approximately 9% eight months after surgery, while another study of 32 CBCT scans from 16 patients reported a decrease in volume of approximately 26% six months post-surgery.\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e Despite differences in surgical techniques and graft materials, most studies indicate a post-surgery reduction in bone graft volume.\u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e Manual segmentation of the sinus floor and graft material in CBCT scans is employed as a method for these assessments, such as in a study that revealed a 25% average decrease in the volumetric dimensions of the bone graft across 20 patients.\u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eThe present study aimed to investigate the potential dimensional changes in graft materials several months after the maxillary sinus elevation procedure. The study aims to assess any changes in the dimensions of grafts over time in individuals who have undergone the maxillary sinus elevation procedure using a combination of xenografts and allografts in the layering technique. Understanding the long-term stability and behavior of graft materials used in oral and maxillofacial surgery is crucial. By determining the extent of dimensional changes that occur in these grafts, we aim to gain valuable insights into their performance and improve patient outcomes. This research will contribute to our understanding of graft behavior and provide important information on the long-term success of this surgical procedure.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cp\u003eThis retrospective, cohort study was based on CBCT scans extracted from dental records of patients in the University School of Dental Medicine, which were selected based on their alignment with the predetermined inclusion and exclusion criteria, from 01\\2009 to 12\\2020. All treatments were performed by 2 experienced periodontists (I.B., G.S.). The study protocol was approved by the Institution Ethics Committee in accordance with Declaration of Helsinki (confirmation no. 003479-1).\u003c/p\u003e \u003cp\u003ePatients included in the study were older than 18 years, underwent LMSA between 01\\2009 and 12\\2020. The procedures were performed only after ensuring there is no active periodontal disease. Only patients who required implant placement on the contralateral side and underwent a third CBCT scan were included. Contraindications to the surgery such as history of head and neck cancer and/or radiotherapy, immune deficiency, and immuno-suppressant medications intake and lack of third (follow-up) CBCT scan served as exclusion criteria for the study.\u003c/p\u003e \u003cp\u003e All patients signed an informed consent before treatment. Surgery was performed under local anesthesia according to the technique described by Boyne and James.\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e A full-thickness access flap was prepared with midcrestal and vertical releasing incisions. A lateral window was created using a low-speed headpiece cooled by sterile physiologic saline. The access window was extended laterally and apically, the sinus membrane was raised, and a particulate bone graft was placed underneath. A combination of approximately 0.5 g deproteinized bovine bone mineral (DBBM), (Bio-Oss, Geistlich) and 2 mL small particulate (250\u0026micro;-1000\u0026micro;), cortico-cancellous mineralized bone allograft (Maxgraft, Botiss) was applied using a bilayer technique. DBBM was placed close to the sinus membrane, while the particulate mineralized bone allograft filled the remaining sinus cavity. The access window was covered with resorbable collage membrane (OsseoGuard, Zimmer Biomet Dental) (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e1\u003c/span\u003eA-D). A periosteal incision was made, and the soft tissues were approximated and sutured with horizontal mattress and single interrupted sutures. Postoperative instructions included rinsing with 0.2% chlorhexidine solution twice daily for 2 weeks, and antibiotics were prescribed for 10 days (Augmentin 875 mg BID, GlaxoSmithKline). Patients who were allergic to penicillin received Dalacin-C 150 mg qid (Pfizer). Analgesics were provided only when needed.\u003c/p\u003e \u003cp\u003eDemographic data, including age, gender, and smoking status, were extracted from the patient\u0026rsquo;s records. Each patient underwent three CBCT scans: the first scan (T0) was performed before LMSA to assess the existing bone level and the anatomical limitations, the second scan (T1) was performed at least five months after LMSA to evaluate the bone level before implant placement, and the third scan (T2) was performed after implant placement and rehabilitation. This was not conducted specifically for the examined site. Instead, it was performed with the aim of facilitating future implant placement on the opposite side. All CBCT scans of the patients were performed between 2009 and 2022 at the Maxillofacial Imaging Institute at the School of Dental Medicine. The examined sites in all patients were exposed to radiation doses of 69\u0026ndash;80 \u0026micro;Sv for a single CBCT scan. From the patients' CBCT scans, linear bone implant measurements were performed at three identical locations for each time point. The first location was the point with the highest augmentation (peak of augmentation), the second location was 4 mm mesial to the peak of augmentation, and the third location was 4 mm distal to the peak of augmentation. The measurement was performed by manually marking the area and calculating the surface area using ImageJ software (US National Institute of Health). Furthermore, the distance from the apex of the dental implant to the peak of augmentation was measured for each patient in the T2 scans (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eLinear regression was used to ascertain the effects of multiple variables on a continuous dependent variable. Possible confounders were added to the regression model to neutralize their effect. One-way ANOVA with post-hoc tests and Bonferroni correction for multiple tests was used to test for differences between groups' means. The Kolmogorov-Smirnov normality test was used to test if a variable follows a normal distribution. Student's t-test was used to test for a difference between the means of two groups on a normal continuous dependent variable. Paired t-test was used when the observations were paired. Pearson's correlation was used to determine the strength and direction of a linear relationship between two continuous normally distributed variables. Spearman's correlation was used to determine the strength and direction of a relationship between two continuous non-normally distributed variables.\u003c/p\u003e \u003cp\u003eP-values were corrected for multiple tests using the Benjamini-Hochberg (BH) method.\u003c/p\u003e \u003cp\u003eDescriptive statistics and statistical analysis were done using SPSS 28 software for Windows (IBM). Power calculation for minimal required study cohort was done using G*Power 3.1.9.4.\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eWe assumed that the correlation between the time between T1 and T2 and the delta between T2 and T1 at the peak augmentation would be 0.6. Then for a one-sided Pearson correlation test, a test significance 0.05 and power 0.8, we would need a sample of 15 patients.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cp\u003eA total of 16 patients (12 females and 4 males) were found eligible for the study. (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e3\u003c/span\u003e) Those availed 48 CBCT scans for the analysis. The mean patient\u0026rsquo;s age was 66 years (52\u0026ndash;79 years, SD\u0026thinsp;=\u0026thinsp;7.946). Among the participants, 2 individuals reported being smokers, with both smoking up to 10 cigarettes a day. All subjects were otherwise healthy. The mean time elapsed between T1 and T2 was 18 months (4\u0026ndash;46 months, SD\u0026thinsp;=\u0026thinsp;12.463). A total of 34 implants were placed, from three distinct types: MIS SEVEN [MIS implant technologies Ltd] (20 implants, 58.8%), LANCE [MIS implant technologies Ltd] (8 implants, 23.5%) and ZIMMER [Zimmer Biomet Dental] (6 implants, 17.7%). Most participants (63%) received implants with a diameter of 3.75mm. Additionally, 36% of participants received implants in the 4.1-4.2mm diameter range (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\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\u003e\u0026ndash; Implant distribution according to position, size, and type\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=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePatient No.\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePosition\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLength [mm]\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eDiameter [mm]\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eType\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eLANCE\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eLANCE\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eZIMMER\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eZIMMER\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eZIMMER\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eZIMMER\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eLANCE\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eLANCE\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eLANCE\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eLANCE\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eLANCE\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMIS SEVEN\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eZIMMER\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eZIMMER\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e#16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eLANCE\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\u003eBetween T1 and T2, changes in the bone dimensions at the examined site were observed. At the peak of augmentation, there was a mean change of -30.89mm\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e (SD\u0026thinsp;=\u0026thinsp;29.751). At a 4mm distal to the peak and at 4mm mesial to the peak the mean volume changes of -26.25mm\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e (SD\u0026thinsp;=\u0026thinsp;32.384) and \u0026minus;\u0026thinsp;27.71mm\u003csup\u003e2\u003c/sup\u003e (SD\u0026thinsp;=\u0026thinsp;28.295) respectively were observed. (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e3\u003c/span\u003e) Based on the results of the repeated-measures Analysis of Variance (ANOVA), there was no statistically significant variation in dimensional change across the evaluated locations (p\u0026thinsp;=\u0026thinsp;0.816) (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eAt the peak of augmentation, the time interval between T1 and T2 had a statistically significant predictive correlation with the bone dimensions change (t = -2.931, p\u0026thinsp;=\u0026thinsp;0.027). Each additional month between T1 and T2 corresponded to a decrease of 1.556 mm\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e (95% CI, -2.723 to -0.388) in the bone dimensions. The mean height of augmentation measured above the implant at the peak of augmentation was 4.86mm (2.04-7.91mm). A regression analysis yielded that augmentation height above the implant is related to gender (t= -2.167, p\u0026thinsp;=\u0026thinsp;0.049) and implant diameter (t\u0026thinsp;=\u0026thinsp;3.251, p\u0026thinsp;=\u0026thinsp;0.012).\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eThis study aimed to investigate dimensional changes in graft materials after maxillary sinus elevation procedures using layers of xenograft and allograft bone filler materials. These materials were arranged in two layers. The radiopaque appearance of xenogeneic bone substitute enables clear demarcation of the graft borderline and its relation to the Schneiderian membrane (Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe results showed a consistent trend of decreasing bone dimensions over time, with a statistically significant reduction between the T1 and T2 scans. This suggests that clinicians and researchers should be aware of these changes and emphasize the need for long-term monitoring to achieve the best outcomes. The average decrease in bone dimensions around the peak of augmentation is consistent with previous studies that have reported a reduction in bone graft volume over time.\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e,\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e. The findings indicate that despite improvements in graft materials and surgical techniques, the post-operative shrinkage of grafts continues to be a challenge.\u003c/p\u003e \u003cp\u003eFurthermore, our results support the idea that time plays a significant role in graft resorption. Specifically, for every additional month between T1 and T2, there was a reduction of 1.556 mm\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e in bone dimensions. The findings of the study are consistent with other studies that also reported a decrease in graft volume following maxillary sinus elevation procedure.\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e,\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eThe choice of graft material has been a focal point in the scientific community, and this study provides further insights into the advantages and disadvantages of xenografts and allografts. Allografts provide an osteoconductive scaffold, and xenografts contribute to graft volume and stability. Both seem susceptible to the general trend of graft resorption and shrinkage.\u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e Based on previous publications, it could be assumed that creating a xenograft outer layer may reduce bone volumetric loss.\u003csup\u003e\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e Yet, a randomized control study comparing graft volume reduction with other materials could clarify the potential contribution of xenograft to dimensional stability. Over time, the observed trend toward dimensional reduction suggests that clinicians must carefully consider the timing between the maxillary sinus elevation procedure and the subsequent implant placement. Although the xenograft remained stable over time, using this combination in the layering technique did not prevent a volumetric change in the height of bone in the sinus over time.\u003c/p\u003e \u003cp\u003eThe influence of gender and implant diameter on augmentation height above the implant is a novel finding. However, drawing definitive conclusions from this study is challenging due to most participants being women. The selection of implant diameter is influenced by bone dimensions and patient-specific treatment planning. The study primarily relied on two-dimensional measurements, which, while informative, are inherently limited in accuracy compared to three-dimensional assessments. To achieve a more comprehensive and precise understanding of graft material volume changes, three-dimensional measurements are required. Such an approach will provide critical insights into the complexities of graft resorption and bone dimensional changes. The analyzed CBCTs present a relatively broad span of follow-up times (4\u0026ndash;46 months, mean 18 months). This variability in timeframe is a result of the treatment plan required for the contralateral sinus. The mean height of augmentation measured above the implant at the peak of augmentation was 4.86mm. Evaluating the remaining bone above the implants in T2 is important in order to demonstrate that no membrane perforation occurred during implant placement, which could have led to the bone volume collapse over time. This study\u0026rsquo;s limitations include a relatively small sample size of 16 patients and a diverse range of time between T1 and T2 scans. Two experienced periodontists conducted all procedures, which may not be applicable to all clinicians. Future research should strive to include a larger and more diverse group. Moreover, differentiation between the allograft and the pristine patient bone may not always be straightforward, particularly several months following the surgical procedure.\u003c/p\u003e"},{"header":"CONCLUSIONS","content":"\u003cp\u003eThe present study offers valuable insights into the long-term behavior of graft materials used in maxillary sinus elevation procedures. While the combination of xenografts and allografts presents clinical advantages, our findings highlight the necessity of ongoing monitoring and consideration of time elapsed between procedures to ensure optimal outcomes. The relationship between implant diameter, gender, and graft resorption coupled with the potential enhancement in accuracy through three-dimensional measurements, also delineates new avenues for future research.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCBCT\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003econe beam computer tomography\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eLMSA\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003elateral maxillary sinus augmentation\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eqid\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003efour times a day\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eConceptualization: I.B., G.S; project administration: D.P and M.S; data curation: P.R; validation: D.P, P.R, G.S; investigation: D.P; formal analysis: D.P. and M.S. analyzed the data; writing \u0026ndash; original draft: M.S, I.B. led the writing; writing \u0026ndash; review \u0026amp; editing: all authors contributed to the writing and editing.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that no funds, grants, or other support were received during the preparation of this manuscript.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eThe authors confirm that there is no associated data included in this manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;Ethics approval\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study protocol was approved by the Institution Ethics Committee (no. 003479-1).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to participate\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWritten informed consent was obtained from the patients.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors have no relevant financial or non-financial interests to disclose.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003e\u003cu\u003eDeclarations of interest:\u003c/u\u003e\u003c/strong\u003e none. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eUmanjec-Korac S, Wu G, Hassan B, Liu Y, Wismeijer D. A retrospective analysis of the resorption rate of deproteinized bovine bone as maxillary sinus graft material on cone beam computed tomography. Clin Oral Implants Res. 2014;25:781\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAra\u0026uacute;jo MG, Lindhe J. Dimensional ridge alterations following tooth extraction. An experimental study in the dog. J Clin Periodontol. 2005;32:212\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCavalcanti MC, Guirado TE, Sapata VM, Costa C, Pannuti CM, Jung RE, C\u0026eacute;sar Neto JB. Maxillary sinus floor pneumatization and alveolar ridge resorption after tooth loss: a cross-sectional study. Braz Oral Res. 2018;32:e64.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNunes LS, Bornstein MM, Sendi P, Buser D. Anatomical characteristics and dimensions of edentulous sites in the posterior maxillae of patients referred for implant therapy. Int J Periodontics Restor Dent. 2013;33:337\u0026ndash;45.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBoyne PJ, James RA. Grafting of the maxillary sinus floor with autogenous marrow and bone. J Oral Surg. 1980;38:613\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGeurs NC, Wang IC, Shulman LB, Jeffcoat MK. Retrospective radiographic analysis of sinus graft and implant placement procedures from the Academy of Osseointegration Consensus Conference on Sinus Grafts. Int J Periodontics Restorative Dent. 2001;21:517\u0026thinsp;\u0026ndash;\u0026thinsp;23.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKaufman E. Maxillary sinus elevation surgery: an overview. J Esthet Restor Dent. 2003;15:272\u0026thinsp;\u0026ndash;\u0026thinsp;82; discussion 283.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMaiorana C, Sigurt\u0026agrave; D, Mirandola A, Garlini G, Santoro F. Sinus elevation with alloplasts or xenogenic materials and implants: an up-to-4-year clinical and radiologic follow-up. Int J Oral Maxillofac Implants. 2006;21:426\u0026ndash;32.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJensen T, Schou S, Svendsen PA, Forman JL, Gundersen HJ, Terheyden H, Holmstrup P. Volumetric changes of the graft after maxillary sinus floor augmentation with Bio-Oss and autogenous bone in different ratios: a radiographic study in minipigs. Clin Oral Implants Res. 2012;23:902\u0026ndash;10.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAthanasiou VT, Papachristou DJ, Panagopoulos A, Saridis A, Scopa CD, Megas P. Histological comparison of autograft, allograft-DBM, xenograft, and synthetic grafts in a trabecular bone defect: an experimental study in rabbits. Med Sci Monit. 2010;16:BR24\u0026ndash;31.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGutwald R, Haberstroh J, Kuschnierz J, Kister C, Lysek DA, Maglione M, Xavier SP, Oshima T, Schmelzeisen R, Sauerbier S. Mesenchymal stem cells and inorganic bovine bone mineral in sinus augmentation: comparison with augmentation by autologous bone in adult sheep. Br J Oral Maxillofac Surg. 2010;48:285\u0026ndash;90.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDel Fabbro M, Testori T, Francetti L, Weinstein R. Systematic review of survival rates for implants placed in the grafted maxillary sinus. Int J Periodontics Restor Dent. 2004;24:565\u0026ndash;77.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKlein GG, Curvello VP, Dutra RA, Sime\u0026atilde;o SP, Santos PL, Gulinelli JL, Filho HN. Bone Volume Changes After Sinus Floor Augmentation with Heterogenous Graft. Int J Oral Maxillofac Implants. 2016;31:665\u0026ndash;71.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKirmeier R, Payer M, Wehrschuetz M, Jakse N, Platzer S, Lorenzoni M. Evaluation of three-dimensional changes after sinus floor augmentation with different grafting materials. Clin Oral Implants Res. 2008;19:366\u0026ndash;72.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTemmerman A, Van Dessel J, Cortellini S, Jacobs R, Teughels W, Quirynen M. Volumetric changes of grafted volumes and the Schneiderian membrane after transcrestal and lateral sinus floor elevation procedures: A clinical, pilot study. J Clin Periodontol. 2017;44:660\u0026ndash;71.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKlijn RJ, van den Beucken JJ, Bronkhorst EM, Berge SJ, Meijer GJ, Jansen JA. Predictive value of ridge dimensions on autologous bone graft resorption in staged maxillary sinus augmentation surgery using Cone-Beam CT. Clin Oral Implants Res. 2012;23:409\u0026ndash;15.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBlock MS, Ducote CW, Mercante DE. Horizontal augmentation of thin maxillary ridge with bovine particulate xenograft is stable during 500 days of follow-up: preliminary results of 12 consecutive patients. J Oral Maxillofac Surg. 2012;70:1321\u0026ndash;30.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBuser D, Dula K, Hirt HP, Schenk RK. Lateral ridge augmentation using autografts and barrier membranes: a clinical study with 40 partially edentulous patients. J Oral Maxillofac Surg. 1996;54:420\u0026ndash;32. discussion 432-3.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003evon Arx T, Buser D. Horizontal ridge augmentation using autogenous block grafts and the guided bone regeneration technique with collagen membranes: a clinical study with 42 patients. Clin Oral Implants Res. 2006;17:359\u0026ndash;66.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFaul F, Erdfelder E, Buchner A, Lang AG. Statistical power analyses using G*Power 3.1: tests for correlation and regression analyses. Behav Res Methods. 2009;41:1149\u0026ndash;60.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCordaro L, Torsello F, Morcavallo S, di Torresanto VM. Effect of bovine bone and collagen membranes on healing of mandibular bone blocks: a prospective randomized controlled study. Clin Oral Implants Res. 2011;22:1145\u0026ndash;50.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"sinus augmentation, bone graft, CBCT analysis","lastPublishedDoi":"10.21203/rs.3.rs-4816739/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4816739/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e \u003cp\u003eDuring sinus augmentation, various bone graft substitutes and/or their combination are used. They have varying rates of remodeling and cause different volume changes in the grafted material. This study aimed to investigate the potential time-dependent dimensional changes in graft materials of xenografts and allografts placed using the layering technique, (xenograft placed close to the sinus membrane, while the bone allograft fills the remaining sinus cavity) following a maxillary sinus elevation procedure.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eCBCT records were available for 16 patients referred for contralateral sinus augmentation and implant placement. In these cases, additional CBCT performed prior to the procedure revealed graft dimensional changes. Linear measurements of the augmented bone grafts were performed at three identical locations at two-time points. Linear regression, one-way ANOVA and Pearson's and Spearman\u0026rsquo;s correlations were used for statistical analysis. P values\u0026thinsp;\u0026le;\u0026thinsp;0.05 were considered statistically significant.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThere was no statistically significant variation in the rate of dimensional change across the different evaluated locations in the augmented graft (p\u0026thinsp;=\u0026thinsp;0.816). At the peak of augmentation, each additional month corresponded to a decrease of 1.556 mm\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e (95% CI, -2.723 to -0.388) in the bone dimensions. The changes of the amount of bone filler material above the implant was related to gender (t= -2.167, p\u0026thinsp;=\u0026thinsp;0.049) and implant diameter (t\u0026thinsp;=\u0026thinsp;3.251, p\u0026thinsp;=\u0026thinsp;0.012).\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eThe combination of xenografts and allografts in maxillary sinus augmentation, applying layer technique, underwent dimensional changes over time and amounted to a 1.5mm\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e reduction per month. More residual bone was observed among female patients and wider implant diameters.\u003c/p\u003e","manuscriptTitle":"Analysis of the dimensional changes in bone grafts after maxillary sinus augmentation procedure.","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-09-04 22:55:17","doi":"10.21203/rs.3.rs-4816739/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"8f7f3e57-7a78-4e52-a544-13f195eb3e86","owner":[],"postedDate":"September 4th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-09-20T03:52:57+00:00","versionOfRecord":[],"versionCreatedAt":"2024-09-04 22:55:17","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4816739","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4816739","identity":"rs-4816739","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}