Recognizing the temporomandibular joint ganglion.

A case report of a cystic preauricular mass that changed in size and position with jaw movement is presented. This tumor proved to be a ganglion of the temporomandibular joint (TM) cyst, which is relatively rare. When a preauricular mass retrudes into the masseter muscle in jaw opening, pathological conditions associated with the TMJ should be considered. Ganglion cysts of the TMJ are a benign pathological entity which can mimic parotid tumors. Temporomandibular joint radiography and perhaps ultrasonography of the region are useful in the preoperative evaluation of preauricular masses. The TMJ ganglion cyst can be successfully treated by direct excision and repair of the joint capsule. This approach avoids the potential morbidity of a superficial parotidectomy.