Tophaceous pseudogout of the temporomandibular joint: a series of 3 cases.

Objective: We report a series of 3 cases of tophaceous pseudogout of the temporomandibular joint (TMJ).

Study Design: Three patients, two men and one woman, ranging in age between 60 and 75 years, presented with unilateral painful swelling of the TMJ area associated with limitation of mouth opening.

Results: Radiographic and computed tomographic images showed opaque masses in the supracondylar region of the TMJ. The preoperative clinical impression was a "neoplastic lesion" in the 3 cases. Microscopic examination revealed numerous deeply basophilic masses of calcified deposits, exhibiting birefringence under polarized light and morphologically consistent with calcium pyrophosphate dihydrate deposition, referred to in these cases as "tophaceous pseudogout."

Conclusion: Tophaceous pseudogout is a rare benign arthropathy that presents with clinical and radiographic features mimicking neoplastic conditions of the TMJ. Therefore, it is recommended that tophaceous pseudogout be considered in the differential diagnosis when a TMJ is involved with "neoplasm-like" lesions clinically and radiographically.