Autonomic and Psychologic Risk Factors for Development of Tinnitus in Patients with Chronic Temporomandibular Disorders

Aims: To investigate the roles of autonomic regulation and psychologic condition in the development of tinnitus in patients with chronic temporomandibular disorders (TMD). Methods: In total, 55 participants (mean age 36.4 ± 12.6 years; 7 men, 48 women) were involved: 13 with no signs of painful TMD or tinnitus (CON), 15 with painful TMD without tinnitus (pTMD), and 27 with both painful TMD and tinnitus (TMDTIN). The Research Diagnostic Criteria for TMD and the Tinnitus Handicap Inventory (THI) were used to classify painful TMD and selfreported tinnitus, respectively. Measures of arterial heart rate (HR) and blood pressure (BP) were assessed at rest and in response to orthostatic challenges, cold-stress vasoconstriction, Valsalva maneuver, and psychologic stress. The sympathetic variables (BP responses to standing, cold stress, and psychologic stress) and parasympathetic variables (HR response to Valsalva maneuver [Valsalva ratio] and active standing [30:15 ratio]) were estimated. Results: Parasympathetic measures demonstrated significant differences between pTMD and TMDTIN. The period of pain duration showed significant positive correlations with BP variables during orthostatic challenges and/or cold stress in both pTMD and TMDTIN. THI scores showed significant positive correlations with results from the psychologic analysis. The range of motion of the mandible demonstrated a greater correlation with results from the psychologic analysis in TMDTIN compared to pTMD. Conclusion: Dysregulated psychophysiologic interactions may affect the development of tinnitus in patients with chronic TMD. Keywords: autonomic nervous system, central nervous system sensitization, comorbidity, temporomandibular disorders, tinnitus