When this group of pain symptoms and deafness were proposed1in 1933 as comprising a symptom complex regularly associated with destruction of the mandibular joint, it was considered as not rare but of infrequent occurrence. Deductions were made from cases presenting an edentulous mouth and extensive destruction of the joint, showing wide overclosure of the jaw. In the first small group there appeared patients with unilateral loss of molar support, however, which demonstrated the pain qualities more clearly and responded more promptly to the proposed solution of the problem; that is, the replacement of adequate molar support on the affected side. During a two year period the study of these cases was continued, and they were drawn not only from a group referred as sinus and ear cases but also from those being studied in dermatology, internal medicine and neurosurgery. The number of proved cases having reached 125, their