In each of 3 patients referred for computed tomographic examinations of the
temporomandibular joint, a gas collection was observed in the inferior spa
ce of the joint. The gas was-observed on the posterosuperior surface of the
mandibular condyle in the open mouth position in each patient. Each of 2 p
atients had saucer-shaped bone resorption of the mandibular condyle adjacen
t to the gas; 1 patient had no remarkable bone abnormality. A history of te
mporomandibular joint puncture or facial trauma was denied by all 3 patient
s.