Articular remodeling in the adult human temporomandibular joint

Abstract

AbstractArticular cartilage can proliferate sufficiently to alter the contours of joints, allowing them to adapt morphologically to various mechanical stresses. This remodeling has been classified into three types based on histologic criteria which were then applied to the temporomandibular joint. This joint has a fibrous type of articular tissue which is converted postnatally into fibrocartilage in the loaded areas. The thickness and cell population of this tissue, and the amount of internal reconstruction in the subchondral bone vary from one part of the joint to another. These changes appear related to the distribution of mechanical stresses in the joint. Conclusions drawn are: The temporomandibular joint shows the following remodeling trends: progressive remodeling on the anterior part of the condyle, medial part of the tubercle, and roof of the mandibular fossa; regressive remodeling on the posterior part of the condyle and on the lateral part of the tubercle. A perforation in the disc causes progressive remodeling on the condyle and regressive remodeling on the tubercle at the perforation site. Articular remodeling merges gradually into osteoarthritis as the articular tissue breaks down. The net effect of remodeling that has become uncompensated or pathologic is: condyle flattened and enlarged, tubercle resorbed, disc perforated, and articular surfaces uneven. If the dentition is not restored or replaced, a high rate of temporomandibular remodeling occurs which will probably continue into osteoarthritis.