Transverse Malocclusion and Temporomandibular Disorders: Verification of the Controversy

Aims: To investigate the transverse dental and skeletal aspects of malocclusion in a sample of temporomandibular disorders (TMD) patients and to assess the correlations of these aspects with the signs and symptoms of TMD. Methods: A total of 150 TMD patients diagnosed according to the Diagnostic Criteria for TMD were divided into five groups: Group 1 (myalgia), Group 2 (disc displacement with reduction [DDWR]), Group 3 (disc displacement without reduction [DDWOR]), Group 4 (degenerative disorders), and Group 5 (subluxation). The transverse occlusion was assessed clinically, and any posterior crossbite present was recorded. Using cone beam computed tomography, several skeletal and dental transverse measurements were evaluated in each patient to diagnose the presence of skeletal posterior crossbite and possible facial and dental asymmetry. One-way analysis of variance was used to compare the means of more than two groups. Pearson correlation coefficient was used to assess the correlations of quantitative continuous variables. Significance level was considered at P .05. Results: Posterior crossbite was found in only 18% of the sample, while 28.7% of the subjects showed transverse skeletal crossbite. All skeletal and dental measurements evaluating symmetry showed no statistically significant differences between the groups except for the occlusal plane cant, which was significantly higher in Group 2 compared to Group 1. Dental and skeletal transverse discrepancies showed no correlation with TMD. Conclusions: Transverse malocclusion is not correlated with the signs and symptoms of TMD. Keywords: facial asymmetry, malocclusion, posterior crossbite, skeletal crossbite, temporomandibular disorders