Relationship of articular soft tissue contour and shape to the underlying eminence and slope profile in young adult temporomandibular joints

Abstract

This study examined whether the overall shape of the articular soft tissue overlying the posterior slope and articular eminence of the temporal bone could be predicted by the underlying osseous contour in a histologic model of 51 central sagittal sections of young adult temporomandibular joints. Articular soft tissue and bone contours were traced, and osseous landmarks identified on the basis of joint geometry. Soft tissue thickness measurements were made under low power light microscopy. Seven categories of articular soft tissue pattern were identified. The soft tissue uniformly followed the osseous contour in only one (14%). A progressive increase in soft tissue thickness from the middle of the posterior slope to the articular crest was the most common pattern (35%) but did not describe most of the sample that was more asymmetric. Pattern was poorly perdicted by the shape and slope of the temporal bone outline or by dental factors that describe anterior guidance and did not relate to disk displacement. The articular soft tissue compensated for flatter eminence slopes and osseous irregularities and maintained an intact surface. This study has clinical implications for radiographic interpretation of disk space, condyle translation pathways, and the integrity of the functional articular surface.