Computed tomography of the normal temporomandibular joint

A study was made in two parts, retrospective (I) and prospective (II), on two samples of 36 and 17 individuals, respectively, who had temporal bone CT studies for reasons unrelated to TMJ pain and dysfunction. Groups I and II had no radiographic signs of TMJ disease and Group II had neither radiographic nor clinical signs of TMJ disease. Both groups were considered to have normal joints. Joint morphometrics for the two groups (I/II) were as follows; transverse condylar dimensions were 18.5/18.1 mm. Condylar angulation averaged 24 degrees/25 degrees and intercondylar distance averaged 83/83 mm while extra condylar distance averaged 118/118 mm. The condyle in the sagittal plane showed a smooth and rounded form with anterior-superior joint space averaging 1.9/1.7 mm while the central-superior joint space averaged 2.3/2.2 mm. The medial-horizontal joint space averaged 3.9/3.7 mm. The slope of the central portion of the articular eminence averaged 60 degrees/60 degrees in the sagittal plane.