Temporomandibular disorders as an etiological factor for tinnitus

Abstract

Tinnitus is the sensation of hearing a sound with no external auditory stimulus present. Tinnitus is very prevalent and increases with increasing age. The most common presentation is high pitched cricket sounds, buzzing or ringing in both ears and often but not always associated with hearing loss. There are many possible causes of tinnitus, but few specific established treatments. Epidemiologic data indicate a frequent association between TMD and tinnitus. Disorders of the masticatory system may exert an influence on tinnitus via mechanical connections between the temporomandibular system and the ear or via neuronal influences. This hypothesis explains how the fusimotor system of the muscles innervated by the trigeminal motor nucleus is affected by inadequacies in the occlusion of the teeth that cause changes in posture and movement of the mandible. Inadequate occlusal contacts give rise to an adapted function of the mandible and the most common compensatory muscular response is hypertonia involving all mandibular muscles, including the tensor tympani. The treatment of tinnitus is very complex and etiologically defined. This article reviews the effect of TMD therapy on tinnitus.