Hearing Assessment in Temporomandibular Disorders: Systematic Review
Introduction: The main signs and symptoms of temporomandibular joint disorders (TMD) are pain in the masticatory muscles, difficulty to perform mandibular movements, joint sounds, and hearing symptoms. Due to the high variability of these signs/symptoms and their intensity is necessary to establish a hearing assessment protocols for patients with TMD.
Objective: To investigate the procedures performed to verify the occurrence of hearing signs/symptoms in patients with TMD, in order to investigate the systematization of protocol that verifies audiological disorders in these patients.
Methods: A bibliographical survey was performed in Lilacs and PubMed with descriptors “Temporomandibular Joint” and “Hearing.” Exclusion criteria were patients with TMD, hearing complaints, and with other impairments; articles that are repeated in different databases or in another language that was not the Portuguese or English; that were not available in full by the system VPN-USP. The selected studies were analyzed for audiological evaluations, results, and conclusion.
Results: Initially, 221 abstracts were selected, but only 17 met the inclusion criteria, published from 1987 to 2013. In the studies, we were observed the following procedures in patients with TMD: otological and vestibular symptoms questionnaire, tinnitus questionnaires (Tinnitus Handicap Inventory; Tinnitus Research Initiative; Tinnitus Sample Case History Questionnaire), visual analog scale (measuring tinnitus intensity), otoscopy, audiometry, auditory brainstem response, tympanometry, acoustic reflex, psychoacoustic characteristics of tinnitus, and evoked-otoacoustic emissions.
Conclusion: There is wide variability of procedures to investigate the existence of hearing signs/symptoms in patients with TMD and suggesting the importance of new studies relating hearing assessment in these patients.