Osteoarthritis of the temporomandibular joint organ and its relationship to disc displacement

To overcome disagreements with regard to the relationship between disc disp lacement and osteoarthritis of the temporomandibular joint (TMJ), the evide nce for suggested disease mechanisms and clinical course of these disorders is reviewed. The TMJ behaves as a complex organ in which biochemical and b iomechanical processes regulate the physiology of cartilage, bone, synovium , ligaments, and synovial fluid. In this concept, TMJ osteoarthritis is an organ failure involving all its structures. The development of as well as r ecovery from disease appears to be intimately related to exceeding and supp orting the adaptive capacity of the tissues that make up the joint organ. L oss of fibrocartilage and inflammation appear to be major pathobiologic pro cesses, while serious doubts exist about the significance of disc position in joint pathology.