[Synovial chondromatosis in the temporomandibular joint: report of 2 cases]

The clinical manifestations, radiographic findings, intraoperative view, histopathologic features of synovial chondromatosis（SC） in the temporomandibular joint (TMJ) were summarized in 2 cases. Preoperative symptoms included preauricular pain（2/2）, swelling（2/2） and limitation of mouth opening (0/2). X-ray findings showed widened joint space. The articular surface destructed and irregular stippled calcifications were seen in the infratemporal fossa by CT scan in one case. MRI showed multiple small nodular formations in the articular cavity. There was no malocclusion and limitation of mouth opening after surgery. As a rare disease of the temporomandibular joint， SC often exists in superior spaces. The clinical manifestations lack specificity. Detection of calcified loose bodies on radiography was helpful to diagnosis, while final diagnosis was dependent on histopathologic examination with characteristic cartilaginous nodules in the synovial membrane.