Tinnitus and Temporomandibular Disorders

Temporomandibular disorders (TMDs) are a group of related disorders of the masticatory system (the masticatory musculature and the temporomandibular joint). The most frequent symptom is pain, usually localized in the muscles of mastication, the preauricular region, and the temporomandibular joint (TMJ). Patients often complain of jaw ache, earache, headache, and facial pain. In addition to pain, patients with these disorders frequently have limited or asymmetric jaw movement and joint sounds that are described as clicking or crepitus (McNeill, 1990). The causes of TMDs remain unclear, and numerous factors have been implicated. The first description of the relationship between TMJ dysfunction and aural symptoms is thought to have been made by Costen in 1934. Costen reported various clinical cases of patients with ear and nasal symptoms; he summarized his findings by stating that hearing tests showed a mild type of catarrhal otitis with eustachian tube involvement (usually simple obstruction). The prognosis of such cases reportedly depended on these factors: (a) the accuracy with which refitted dentures relieved the abnormal pressure on the joint; and (b) the extent of the injury to the tube and to the condyle, meniscus, and joint capsule. A more general acknowledgement of the relationship between ear symptoms and TMJ dysfunction was subsequently made (Costen, 1934, 1936, 1944). Sicher reported that from an anatomical perspective, the eustachian tube cannot be compressed during the closure of the mandible; neither can the opening action of the tensor palati muscle on the tube be impaired in this condition, making Costen’s theory impossible (Sicher, 1948). Schwartz theorized that contractive muscle spasms may cause pain as a direct result of myofascial trigger mechanisms and by referred routes (Schwartz, 1956).