Association of autonomic function with temporomandibular disorders

Abstract

Masticatory muscles and temporomandibular joints (TMJs) are essential components of the masticatory system and temporomandibular disorders (TMD) is the term used for painful conditions and disturbances of the masticatory system and its related structures. The etiology of TMD is multifactorial but one of the predominant conceptions is the biopsychosocial theory yet there is a lot of interest towards the connection of autonomic function and TMD. Baroreflex and heart rate variability (HRV) are examples of autonomic variables that are controlled autonomically by the autonomic nervous system (ANS). Baroreflex regulates blood pressure whereas HRV is used to assess ANS function. This literature review reveals that higher HR, HR at rest and reduced HRV are associated with TMD. Pain perception and modulation are also found to be altered in TMD patients which appears as hypersensitivity of the nervous system. There is also evidence that dysfunction of the sympathetic nervous system function is associated with TMD and TMD subjects have altered brain function in response to certain events.