Morphology of the mandibular fossa and the articular eminence in temporomandibular joints with anterior disk displacement.

The depth, length, and depth:length ratio of the mandibular fossa, and the angles of the posterior slope of the articular eminence were measured for 91 temporomandibular joints (TMJ) with anterior disk displacement (ADD) in 79 female patients with TMJ dysfunction. As a control, 48 joints in 24 females without TMJ dysfunction were similarly measured. One of the angeles of the posterior slope of the articular eminence was larger for joints with ADD than for the controls (P < 0.01, Student's t-test). There were no other statistically significant differences between the two groups. Among the 91 joints with ADD, there was no statistically significant difference in any variable between joints with ADD with reduction (n = 46) and those with ADD without reduction (n = 45); likewise, there was no association between the magnitude of angle of the posterior slope of the articular eminence and overjet, overbite, canine relationship, or molar relationship.