Abstract
OBJECTIVE: Tinnitus is frequently reported in individuals with temporomandibular disorders (TMD), especially in the somatosensory subtype, which can be modulated by afferent input from orofacial and cervical structures. While the impact of orofacial dysfunctions on tinnitus has been explored, the potential reverse relationship remains understudied. To investigate the association between somatosensory tinnitus and orofacial myofunctional condition in individuals with TMD. METHODOLOGY: An observational, cross-sectional study was conducted with 47 adults aged 18 to 45 years diagnosed with TMD and self-reported tinnitus. Participants were assessed in a university-based outpatient setting. The primary outcome was the orofacial myofunctional condition, measured using the Orofacial Myofunctional Evaluation with Scores (OMES) protocol. Additional variables included tinnitus intensity and frequency (via acuphenometry), tinnitus-related distress (Tinnitus Handicap Inventory - THI), cervical disability (Neck Disability Index - NDI), craniofacial pain and disability (Craniofacial Pain and Disability Inventory - CF-PDI), and psychological symptoms (Hospital Anxiety and Depression Scale - HADS). Data were analyzed using Spearman correlation and multiple linear regression, and adopted statistical significance was set at p<0.05. RESULTS: OMES scores showed negative correlations with tinnitus intensity (r=-0.353), THI, NDI, CF-PDI, and age. In the final regression model, only tinnitus intensity remained a predictor of OMES score (β =-0.356; R2=0.127, Confidence Interval -0.20 to -0.02), indicating that greater tinnitus intensity was associated with poorer orofacial myofunctional condition. CONCLUSION: These findings suggest that somatosensory tinnitus may negatively impact orofacial motor function in patients with TMD, underscoring the need for integrated and multidisciplinary assessment approaches.