Temporomandibular Joint Herniation Into the External Auditory Canal: Two Cases Involving a Persistent Foramen Tympanicum.

A congenital bony defect of the external auditory canal (EAC) may cause temporomandibular joint (TMJ) herniation into the EAC. This rare condition is known as persistent foramen tympanicum. We report 2 cases of symptomatic TMJ herniation through a patent foramen tympanicum. The patients complained of mastication-induced tinnitus. Otoscopic examination revealed that a whitish protruding mass at the anterior wall of the EAC bulged when the patients closed their mouths. After conservative managements such as avoidance of chewing foods on the affected side for 2 months, mastication-induced tinnitus disappeared and the size of protruding mass was decreased in one of the patients. Surgical repair of the bony defect has been the treatment of choice. In cases when symptoms are trivial and patients do not want surgical treatment, however, conservative management would be a sound alternative.