Journal of the World Federation of Orthodontists最新文献

{"title":"Environmental footprints in orthodontics: The World Federation of Orthodontists' white paper on sustainable practices, challenges and research imperatives.","authors":"Theodore Eliades, Samar M Adel, Akyalçin Sercan, Phimon Atsawasuwan, Kelvin Wc Foong, Anastasia Hiskia, Nearchos Panayi, Nikolaos Silikas, Allareddy Veerasathpurush, Adith Venugopal, Aron Dellinger, Letizia Perillo, Nikhillesh Vaiid","doi":"10.1016/j.ejwf.2025.06.003","DOIUrl":"https://doi.org/10.1016/j.ejwf.2025.06.003","url":null,"abstract":"<p><p>This World Federation of Orthodontists (WFO) white paper addresses the escalating environmental impact of orthodontic practices, synthesizing expert perspectives on sustainable transformation. The paper critically evaluates the environmental footprints associated with orthodontic materials, energy consumption, and waste management across diverse global settings. It examines the impact of both traditional and emerging digital technologies, highlighting the challenges of material selection, recycling limitations, and energy-intensive procedures. Recommendations focus on adopting eco-friendly materials, minimizing resource consumption, promoting responsible waste disposal, and integrating digital workflows to improve efficiency. It emphasizes the need for standardized guidelines and collaborative efforts among orthodontists, researchers, manufacturers, and policymakers to achieve a more sustainable future for the profession. The discussions in this manuscript delve into various aspects, including material use, waste management, and potential avenues for sustainable transformation of orthodontic practices. The goal is to foster a collective commitment to reducing the environmental impact of orthodontics, ensuring a healthier planet for future generations.</p>","PeriodicalId":43456,"journal":{"name":"Journal of the World Federation of Orthodontists","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144660698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"World Federation of Orthodontists social media guidelines: Ensuring accuracy, reliability, and objectivity in online orthodontic information.","authors":"Narayan H Gandedkar, Bryce Ph Lee, Valmy Pangrazio-Kulbersh, Reem Alansari, Jorge L Castillo, Ricardo M Cruz, Derya G Çakan, Kelvin Wc Foong, Jae H Park, Young G Park, Aron Dellinger, Letizia Perillo, Allan R Thom, Nikhillesh Vaiid","doi":"10.1016/j.ejwf.2025.06.002","DOIUrl":"https://doi.org/10.1016/j.ejwf.2025.06.002","url":null,"abstract":"<p><strong>Background: </strong>The World Federation of Orthodontists (WFO) recognizes the growing impact of online media in shaping public understanding of orthodontics. In response to the proliferation of misinformation and disinformation, particularly on digital platforms, the WFO has developed comprehensive guidelines aimed at ensuring accuracy, objectivity, and ethical standards in online orthodontic content. These guidelines serve to inform WFO fellows and affiliates involved in creating or managing web-based orthodontic resources.</p><p><strong>Methods: </strong>A detailed policy framework was established by the WFO to address key elements of digital communication. These include content definition, site ownership and access, payment structures, privacy protocols, sponsorship disclosures, funding transparency, and ethical advertising practices. Special emphasis was placed on promoting source verification, critical appraisal of content, and user engagement strategies to combat misinformation. The policy was developed through expert consensus and informed by best practices in health communication and evidence-based dentistry.</p><p><strong>Results: </strong>The guidelines provide a structured approach to enhancing the credibility and reliability of online orthodontic information. By delineating clear standards for ethical content creation and dissemination, the WFO aims to safeguard public trust and support informed decision-making. The policy addresses modern challenges posed by social media and other user-driven platforms, offering practical strategies for orthodontists to promote evidence-based information and patient education. A commitment to regular review ensures the framework remains adaptive to the evolving digital environment.</p><p><strong>Conclusions: </strong>The WFO online content guidelines establish a robust foundation for ethical, accurate, and transparent communication in orthodontics. By adhering to these principles, WFO members and affiliates can actively contribute to reducing misinformation, enhancing patient understanding, and upholding the integrity of the profession. Ongoing updates will ensure alignment with technological advancements and emerging communication trends.</p>","PeriodicalId":43456,"journal":{"name":"Journal of the World Federation of Orthodontists","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144643787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical deterioration of passive self-ligating lingual brackets under simulated prolonged use: An in vitro study.","authors":"Prasad Nalabothu, Konstantina Papadopoulou, Michel Dalstra, Giuseppe Scuzzo, Carlalberta Verna","doi":"10.1016/j.ejwf.2025.05.007","DOIUrl":"https://doi.org/10.1016/j.ejwf.2025.05.007","url":null,"abstract":"<p><strong>Background: </strong>Passive, self-ligating lingual brackets are favored in Orthodontics for their simplified mechanism, eliminating the need for elastomeric and metallic ligatures. However, limited data exists on the effects of repeated use on their mechanical durability. An understanding of these effects is essential to ensure their long-term clinical performance. This study evaluates the mechanical degradation of the sliding cap locking mechanism of passive self-ligating lingual brackets after repeated opening and closing cycles.</p><p><strong>Methods: </strong>In this in vitro study, 60 ALIAS mandibular incisor brackets were subjected to repeated opening and closing cycles (5, 10, 20, and 40 cycles). Mechanical tests were performed using an Instron 3344 electronic universal testing machine to measure maximum force at failure (F_max), energy absorption at F_max (U_max), and initial stiffness of the bracket opening mechanism (K).</p><p><strong>Results: </strong>The sliding cap remained functional throughout the test period. However, a significant reduction in F_max, U_max, and K over multiple opening and closing cycles. F_max showed a significant reduction after 5 opening and closing cycles (P = 0.0069), U_max after 10 cycles (P = 0.0243), and K showed after 5 cycles (P = 0.0002). The F_max reached a plateau at about 8-10 Newtons after 10 cycles, U_max at about 2.0 mJ (millijoules), and K at 50 N/mm after 10 cycles.</p><p><strong>Conclusions: </strong>The study highlights significant advantages of passive self-ligating lingual brackets, showcasing their excellent initial performance. While ALIAS brackets may experience minor mechanical deterioration of the properties, their overall performance remains strong enough for entire duration of orthodontic treatment (2-3 years).</p>","PeriodicalId":43456,"journal":{"name":"Journal of the World Federation of Orthodontists","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144565396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anteroposterior displacements of the jaws and incisors relative to the forehead during growth: A longitudinal cephalometric analysis of untreated subjects with Class I occlusions.","authors":"Will A Andrews, Adam J Rudmann","doi":"10.1016/j.ejwf.2025.05.006","DOIUrl":"https://doi.org/10.1016/j.ejwf.2025.05.006","url":null,"abstract":"<p><strong>Objective: </strong>To assess anteroposterior (AP) displacements of the jaws and incisors relative to the forehead in untreated growing subjects with normal (Class I) occlusions.</p><p><strong>Materials and methods: </strong>Serial lateral cephalograms from 74 untreated subjects (37 female, 37 male) with Class I dental relationships were obtained from the AAOF Craniofacial Growth Legacy Collection. Mean age at T1 was 9.9 years; T2 was 17.6 years. T1 tracings were secured over millimeter graph paper with Frankfort Horizontal aligned horizontally. Superimpositions were guided by anterior cranial base structures, then shifted along Frankfort Horizontal so that glabella on T1 and T2 shared a common vertical plane (Glabella-Vertical [GV]). AP displacements of Point A (Pt A), Point B (Pt B), maxillary central incisor's FA point (U1FA), and mandibular central incisor's FA point (L1FA) were measured relative to GV. Changes in occlusal plane (OP) inclinations were also measured.</p><p><strong>Results: </strong>Average AP displacement at Pt A was -0.47 mm; Pt B +0.71 mm; U1FA +0.32 mm; and L1FA +0.82 mm. OP inclination decreased 2.3⁰ on average. Displacement of L1FA was significantly different between genders (M, +1.16 mm; F, +0.47 mm; P = 0.04). No significant differences between genders were found for any other variable.</p><p><strong>Conclusions: </strong>AP jaw and incisor positions were effectively static relative to GV during normal growth between ages 9 and 18 with untreated Class I occlusions. On average, no site underwent AP displacement relative to GV that exceeded 1 mm. The OP tended to rotate counterclockwise. In subjects with Class I dental relationships, pretreatment jaw, and incisor positions do not undergo significant AP changes relative to GV during growth after 9 years of age regardless of gender. GV could thus serve as a reliable AP diagnostic landmark in growing patients.</p>","PeriodicalId":43456,"journal":{"name":"Journal of the World Federation of Orthodontists","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144565395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3D assessment of morphological changes, maxillary central incisor-incisive canal relationship, and root resorption in extraction fixed appliance therapy considering demographic and skeletal classifications.","authors":"Remsh Khaled Al-Rokhami, Zhihua Li, Sarraj Ashour, Sadam Elayah, Bin Yang, Xin Zhao, Jingke Liu, Karim Ahmed Sakran","doi":"10.1016/j.ejwf.2025.05.005","DOIUrl":"https://doi.org/10.1016/j.ejwf.2025.05.005","url":null,"abstract":"<p><strong>Background: </strong>This study aimed to assess changes in morphology, the relationship between the maxillary central incisor (U1) and the incisive canal (IC) and estimate root resorption following extraction orthodontic treatment with fixed appliances, considering gender, age, and skeletal sagittal and facial classifications.</p><p><strong>Methods: </strong>The sample comprised eighty-four maxillary central incisors from 42 patients treated with maxillary incisors retraction using fixed appliances with first premolars extraction. Measurements, including IC width, root-IC distance, cortical bone width, IC height, and root resorption, were taken before (T1) and after (T2) treatment at specified heights (H1, H2, and H3; 2, 4, and 6 mm above the labial cementoenamel junction of U1).</p><p><strong>Results: </strong>Significant differences in IC width, U1 length, and U1 root-IC distance were observed across genders, age groups, and skeletal classifications. Root resorption was greater in females (2.60 ± 1.82 mm vs. 1.25 ± 1.20 mm, P = 0.008), adults (2.53 ± 1.71 mm vs. 1.28 ± 1.45 mm, P = 0.009), Class II subjects (2.30 ± 1.86 mm vs. 1.47 ± 1.22 mm, P = 0.040), and the high angle facial group (3.41 ± 1.49 mm vs. 1.10 ± 1.23 mm vs. 0.90 ± 0.75 mm, P < 0.001). Root-IC proximity increased after treatment, showing a positive correlation with resorption, especially at H2 level for approximation (66.7%) and contact (31%), and at the H1 level for invasion (25%). Multivariate regression identified U1 tooth movement and IC height as key factors in negative U1-IC relationships.</p><p><strong>Conclusions: </strong>Extraction orthodontic treatment with fixed appliances significantly impacts the U1-IC relationship and contributes to root resorption, with variations across demographic and skeletal groups. These findings underscoring the need for precise treatment planning to reduce risks of root resorption and unfavorable U1-IC proximity.</p><p><strong>Clinical relevance: </strong>These findings enhance orthodontic treatment planning by identifying factors influencing root resorption and preserving dental health during anterior teeth retraction.</p>","PeriodicalId":43456,"journal":{"name":"Journal of the World Federation of Orthodontists","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144561355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Open bite treatment through delicate rotation of occlusal and mandibular planes with clear aligners: A case report.","authors":"Yeerpan Ailikamu, Xinyu Yan, Xiaoyue Han, Donger Lin, Xi Zhao, Wenli Lai, Hu Long","doi":"10.1016/j.ejwf.2025.05.004","DOIUrl":"https://doi.org/10.1016/j.ejwf.2025.05.004","url":null,"abstract":"<p><p>This case report presents a successful treatment of an 18-year-old male patient with skeletal open bite and mild dental crowding using clear aligners. The treatment plan involved a series of approaches: sequentially intruding the posterior teeth, extruding the maxillary anterior teeth, and implementing counterclockwise rotation of the mandibular plane and clockwise rotation of the occlusal plane to achieve desirable functional and esthetic outcomes. This comprehensive strategy resolved the anterior open bite and established Class I canine and molar relationships. After 2 years of treatment with a total of 64 (39 + 25) sets of clear aligners and a 1-year follow-up, all treatment objectives, including the resolution of open bite, proper alignment of teeth, mandibular repositioning, and improvement of lateral profile, were successfully achieved. This case demonstrates the effectiveness and advantages of clear aligners in treating anterior open bite. It not only provides a esthetically appealing and comfortable wearing experience, but also achieves remarkable outcomes in complex cases.</p>","PeriodicalId":43456,"journal":{"name":"Journal of the World Federation of Orthodontists","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144545389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of direct and indirect skeletal anchorage for maxillary molar distalization in Class II malocclusion: A prospective clinical study.","authors":"Zeyad M Ali, Marwa S Shamaa, Mohammad H Mohammad","doi":"10.1016/j.ejwf.2025.05.002","DOIUrl":"https://doi.org/10.1016/j.ejwf.2025.05.002","url":null,"abstract":"<p><strong>Background: </strong>To compare the dentoalveolar and skeletal changes induced by the direct bone-anchored pull distal slider (PDS) and the indirect bone-anchored dual force distalizer (DFD) in Class II malocclusion patients.</p><p><strong>Materials and methods: </strong>Twenty subjects (mean age: PDS = 12.8 ± 0.9 years, DFD = 12.9 ± 1 years) were randomly assigned to either the PDS or DFD group. Both appliances employed temporary skeletal anchorage devices to achieve molar distalization. Lateral cephalometric radiographs and dental casts were analyzed before (T1) and after (T2) treatment to evaluate skeletal and dental effects.</p><p><strong>Results: </strong>Both devices successfully distalized the maxillary first molars (PDS = 7 ± 1 months, DFD = 9 ± 2 months). The distalization amounts were not significantly different (P = 0.339). However, the PDS group exhibited minimal distal tipping (1.75° ± 0.63°, P < 0.001), while the DFD group showed mesial tipping (2.27° ± 5.37°, P = 0.270). The PDS group demonstrated significant maxillary incisor retroclination (-3.21° ± 0.99°, P < 0.001), whereas the DFD group exhibited significant proclination (2.95° ± 1.83°, P = 0.003) and mesial movement (0.91 ± 0.51 mm, P = 0.001). Additionally, the PDS group experienced spontaneous distal premolar drifting, while the DFD group showed mesial movement and tipping of the premolars.</p><p><strong>Conclusion: </strong>Both PDS and DFD effectively distalized maxillary molars, but the PDS provided better control by minimizing tipping and anchorage loss, while the DFD caused anterior anchorage loss.</p>","PeriodicalId":43456,"journal":{"name":"Journal of the World Federation of Orthodontists","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144327173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effectiveness of Mini-screw and Nance palatal arch for anchorage control following segmental maxillary canine retraction in adolescents with angle Class I crowding using 3D digital models: A randomized clinical trial.","authors":"Sanjeev Verma, Vinay Kumar, Raj Kumar Verma, Satinder Pal Singh, Shagun Sharma","doi":"10.1016/j.ejwf.2025.04.003","DOIUrl":"https://doi.org/10.1016/j.ejwf.2025.04.003","url":null,"abstract":"<p><strong>Objectives: </strong>To compare anchorage control and treatment duration between Mini-screws and the Nance palatal arch during segmental canine retraction in adolescents.</p><p><strong>Trial design: </strong>Two-arm, parallel-group randomized controlled trial.</p><p><strong>Methodology: </strong>Fifty patients (11-18 years) requiring first premolar extraction were randomly assigned to Group 1 (Nance palatal arch) or Group 2 (Mini-screw) in the ratio of 1:1. Eligibility criteria included Angle's Class I molar relation, tooth material arch length discrepancy more than 10 mm, requiring first premolar extraction. Allocation was concealed using sequentially numbered, opaque, sealed envelopes. Pretreatment and postretraction digital models were analyzed after individual canine retraction with Burstone's T-loop using 3-matic software. t tests were used to assess tooth movement, and the Mann-Whitney test was employed to evaluate treatment duration (P < 0.05).</p><p><strong>Results: </strong>All 25 patients in the Nance group completed the trial. Two patients in the Mini-screw group were excluded due to screw loosening (n = 23 analyzed). The mean distal canine movement was similar in both groups, but molar mesial movement was significantly lower in Group 2 (0.68 and 0.41 mm) than in Group 1 (1.68 and 1.61 mm). The treatment duration was significantly less Group 2 (173.2 days) compared to Group 1 (186.0 days).</p><p><strong>Harms: </strong>No harms were reported in the trail.</p><p><strong>Conclusion: </strong>Although the mesial movement of molars was significantly less for the Mini-screws, the Nance palatal appliance was clinically equally effective in reinforcing the distal movement of canines. The differences in anchorage loss between the two modalities were small, and clinical judgment is thus imperative for decision-making and planning for absolute anchorage with a Mini-screw.</p>","PeriodicalId":43456,"journal":{"name":"Journal of the World Federation of Orthodontists","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144327174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long-term stability of dental arch widths after extraction and nonextraction orthodontic treatment: A retrospective cohort study.","authors":"Theodora T Giannakopoulou, Alexandra K Papadopoulou, Dan Mike Busenhart, Theodore Eliades, Spyridon N Papageorgiou","doi":"10.1016/j.ejwf.2025.05.001","DOIUrl":"https://doi.org/10.1016/j.ejwf.2025.05.001","url":null,"abstract":"<p><strong>Background: </strong>Dental arch width is considered biologically determined and is associated with a balanced occlusion. However, it is often actively altered during orthodontic treatment and these modifications are associated with postorthodontic relapse. The purpose of this study was to assess the long-term dental arch width changes among patients treated orthodontically with fixed appliances and assess the effect of dental extractions.</p><p><strong>Methods: </strong>Young (<18 years) patients with malocclusion, who had been treated orthodontically with 0.018\"-slot edgewise fixed appliances, were included in this retrospective longitudinal study. The maxillary/mandibular intercanine, interpremolar, and intermolar widths were digitally measured before treatment (T1), at debond (T2), and an average of 7 years post-debond (T3). Data was analyzed statistically at 5% with regression modeling, while a subsample of borderline patients was analyzed to assess the effect of extractions on long-term stability.</p><p><strong>Results: </strong>A total of 104 patients were included (59.6% female; 11.5-year-old at T1), 39.4% (41/104) of which were treated with premolar extractions. All dental arch widths were increased during fixed appliance treatment, with considerable differences between extraction and nonextraction cases (P < 0.05 in all cases). On average 7 years post-debond, nonextraction cases showed significant relapse in intermolar width, while intercanine and interpremolar widths remained stable. After baseline matching of extraction/nonextraction cases, tooth extractions were not associated with post-treatment relapse (P > 0.05). Treatment-related (T1-T2) increases in all three dental arch widths were associated with post-treatment (T2-T3) relapse for both jaws, with 0.20-0.34 mm T2-T3 relapse for each additional 1 mm of width increase during T1-T2.</p><p><strong>Conclusions: </strong>Modest dental arch width increases during fixed appliance treatment showed satisfactory stability in the long term, while greater archwire expansion was associated with increased relapse.</p>","PeriodicalId":43456,"journal":{"name":"Journal of the World Federation of Orthodontists","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144303158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Condylar volume changes in class II division 2 cases treated with unlocking the mandible using clear aligners.","authors":"Hanie Morsi, Karla Carpio Horta, William Wiltshire, Giseon Heo, Tarek El-Bialy","doi":"10.1016/j.ejwf.2025.04.004","DOIUrl":"https://doi.org/10.1016/j.ejwf.2025.04.004","url":null,"abstract":"<p><strong>Introduction: </strong>Class II Division 2 malocclusion involves retroclined maxillary incisors and deep overbite, often accompanied by mandibular retrusion. \"Unlocking\" the mandible by proclining the maxillary incisors, correcting the deep bite, and expanding the maxillary arch has been used to treat this malocclusion. However, the impact of this treatment, using Invisalign® clear aligners, on condylar volume remains unclear. This study evaluates three-dimensional changes in condylar volume after using Invisalign® to unlock the mandible in Class II Division 2 growing patients.</p><p><strong>Methods: </strong>Cone-beam computed tomography (CBCT) data were collected from 22 adolescent patients (11 in the treatment group; 11 in the control group) at T1 (pre-treatment) and T2 (1.5-2 years post-T1). Dolphin imaging software was used for cephalometric tracing, while 3D Slicer and ITK-SNAP software calculated condylar volume. Repeated measure ANOVA compared condylar volume changes, and Pearson's Correlation Coefficient assessed the relationship between condylar volume change and ANB angle in the treatment group.</p><p><strong>Results: </strong>Both groups showed significant condylar volume increases between T1 and T2 (treatment: P < 0.001, 127.45 ± 30.97, control: P = 0.015, 98.8 ± 36.31), with no significant difference between groups at T1 (P = 0.289, 89.19 ± 81.2) or T2 (P = 0.167, 117.9 ± 81.7). The change in ANB angle did not correlate with the condylar volume increase in the treatment group (Pearson's R = -0.15, P = 0.681).</p><p><strong>Conclusion: </strong>Unlocking the mandible successfully corrected Class II Division 2 malocclusion, but condylar volume increases in both groups were likely due to normal growth rather than treatment. Condylar volume change was not correlated with malocclusion correction.</p>","PeriodicalId":43456,"journal":{"name":"Journal of the World Federation of Orthodontists","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144250132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}