Three-dimensional morphologic changes in the temporomandibular joint in asymptomatic patients who undergo orthodontic treatment: A systematic review

ObjectiveThis systematic review aimed to summarize the morphologic changes in the temporomandibular joint (TMJ) in patients who underwent orthodontic treatment and were assessed by 3-dimensional (3D) imaging techniques (e.g., magnetic resonance imaging, cone beam computed tomography, and multidetector computed tomography).Study designThe authors searched PubMed, Web of Science, and Embase databases to identify original articles from 2014 to 2021 containing keywords for morphologic changes in the TMJ, orthodontic treatment, and three-dimensional imaging methods. Prospective and retrospective studies, including observational, cross-sectional, randomized, and nonrandomized clinical trials, cohort studies, and case-control studies, were reviewed. The review was conducted in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The risk of bias was assessed in studies selected for the full-text review.ResultsThe search strategy yielded 294 publications. After an initial screening and the application of exclusion criteria, 13 studies were selected for the final review.ConclusionDifferences were found in condylar positioning, typically in an anterior position; condylar morphology, primarily with increased diameter or head height; and articular disk position within the anterior-posterior plane post-treatment. Changes in the glenoid fossa were not consistent between the studies. The overall risk of bias among studies was moderate. The influence of orthodontic treatment on morphologic changes in the TMJ remains unclear.