Os padrões faciais nas variações anatômicas das articulações temporomandibulares

Abstract

Objective: This study is divided into two articles, whose main objective was to analyze the correlations between distinct facial patterns and the anatomical variations of the temporomandibular joint structures.Methodology: Study 1 is a systematic review whose objective was to investigate the potential association between different facial types and the presence of temporomandibular disorder. Observational studies (cross-sectional and cohort) that evaluated adults diagnosed with TMD based on DC/TMD or RDC/TMD criteria and that reported facial morphological classification were included. The risk of bias was assessed using the Joanna Briggs Institute (JBI) tool. Study 2 is a cross-sectional study based on the analysis of 627 radiographs from 410 women and 323 men, with a median age of 15 years. Two evaluators collected data from panoramic radiographs and cephalometric tracings in lateral teleradiographs performed by an orthodontist trained in Radiology. All exams were acquired with the Orthophos SG 2D/3D equipment (Dentsply Sirona Inc.), comparing the differences between sexes in terms of linear and angular dimensions. The variables measured included the morphology of the condyle, coronoid process, coronoid notch, as well as Co-Gn distance, and four linear measurements: condylar width and height and mandibular ramus width and height, in addition to cephalometric angles: FMIA, SNA, SNB, and ANB. Results: In Study 1, after analyzing 38 studies, there was a tendency of association between hyperdivergent facial patterns, mandibular retrognathism, and posterior mandibular rotation with a higher prevalence of painful TMD, mainly of muscular origin. The relationship between malocclusion and TMD proved inconsistent, although some Class II subgroups showed a higher frequency of symptoms. The heterogeneity in cephalometric methods and diagnostic criteria limited direct comparison between studies. Study 2 evidenced an association of maxillary length with the length and width of the condyle and mandibular ramus. The vertical facial pattern was inversely associated with both condylar and ramus width and length. Mandibular retrognathism was inversely associated with condylar length and mandibular ramus width, while prognathism showed proportional association with the same. Male individuals showed significantly higher values of ramus length and width, as well as condylar width. Conclusion: Both articles confirmed the hypothesis that there is an association between facial pattern and condylar morphometry, however it should not yet be considered an autonomous predictor but may contribute to the improvement of cephalometric analysis and guide more individualized therapeutic approaches, especially in cases involving temporomandibular disorders or orthognathic interventions.