The computerized tomographic features of TMJ bony ankylosis. In A, the red circle refers to the bony fusion area located in the lateral part of the joint, in this area, a radiolucent zone can be observed. The green circle refers to the atrophic condylar head and rudimentary joint space located in the medial part of the joint. In B, the red circle shows osteosclerosis in the bony fusion area, and a radiolucent zone can also be observed in this area. The green arrow indicates that bone mineral density and morphology of the bone marrow cavity in the non-bony fusion area were normal. In A and B, the white arrows indicate excessive bone formation around the joint. Note in the radiolucent zone, no scattered calcified dots can be found.