Relationship between Mediotrusive Occlusal Contacts and Temporomandibular Disorders in Young Adults without Psychosocial Disorders: A Case-Control Study.

Aim: Temporomandibular disorders (TMDs) are multifactorial pathologies often associated with pain, muscle dysfunction, and joint alterations. Mediotrusive (MT) occlusal contacts have been implicated in TMDs due to their potential to alter mandibular biomechanics and masticatory patterns. However, the strength of this association, especially in individuals without psychosocial disorders, remains unclear. The aim was to investigate the relationship between MT occlusal contacts and acute TMDs symptomatology in young adults without psychosocial disorders.

Materials and methods: This case-control study included 116 university students aged 18-30 years, divided into cases (n = 58) with TMDs and controls (n = 58) without TMDs. The Diagnostic Criteria for TMDs were used for diagnosis. MT occlusal contacts were evaluated using 12 µm Arti-Fol tape. Guided lateral mandibular movements were performed to assess their role in TMD symptomatology. Statistical analyses, including Chi-square tests and multivariable logistic regression, were conducted to assess the association between MT contacts and TMDs, adjusting for confounders such as age, gender, angle classification, and retruded contact position to maximum intercuspation (RCP-MI) discrepancies ≥2 mm. Statistical significance was set at P < 0.05.

Results: MT occlusal contacts were significantly associated with TMDs (P = 0.003). The adjusted odds ratio (OR) for individuals with MT occlusal contacts was 3.70 (95% confidence interval (CI): 1.58-8.66). This association was strongest at short lateral movement trajectories, particularly at 0.5 mm (P = 0.013, OR=2.63) and 1 mm (P = 0.002, OR=4.56). Class II malocclusion and RCP-MI discrepancies ≥2 mm were also significantly associated with TMDs in adjusted models.

Conclusion: MT occlusal contacts are associated with acute TMDs symptomatology in young adults without psychosocial disorders, particularly during short lateral mandibular movements. However, their predictive value is low, and adaptive mechanisms likely mitigate their long-term effects. This study does not support routine occlusal therapy for managing these contacts in TMD patients. Future longitudinal research should explore chronicity, digital methods for occlusal recording, and the interplay between MT contacts and other etiological factors.