Platelet-Rich Plasma vs Corticosteroid Injection as Treatment for Degenerative Pathology of the Temporomandibular Joint

1.0 BACKGROUND AND HYPOTHESES 1.1 Osteoarthritis is a continuous and entirely physiologic adaptive process that occurs in every joint. These include the replication of cells that produce matrix, enzymes, protease inhibitors, cytokines, and other peptides. Along with the synthesis of new tissue there is a release of breakdown products into the synovial fluid. Enzymes and phagocytes are required to clear these breakdown products. Normal tissue turnover involves synthesis and breakdown in well-regulated balance. In the degenerative state this balance is upset producing inflammation-derived alterations to the synovium, cartilage, capsule, tendons, and bone. Common causes of such alterations include increased loading, physical stress, and traumatic injury to the joint. 1.2 The rationale for the use of corticosteroids in temporomandibular joint therapy is that they inhibit prostaglandin synthesis and decrease the activity of collagenase and other enzymes that degrade the articular cartilage. Platelet rich plasma is a novel therapeutic agent that has several potential advantages over corticosteroids for the treatment of degenerative pathology of the temporomandibular joint. Platelet rich plasma has been shown to have anti-inflammatory, analgesic, and anti-bacterial properties. It also restores intra-articular hyaluronic acid, increases glycosaminoglycan condrocyte synthesis, balances joint angiogenesis, and provides a scaffold for stem cell migration. Autologous platelet rich plasma injections for treatment of knee cartilage degenerative lesions and osteoarthritis have shown longer efficacy than hyaluronic acid injections in reducing pain and recovering articular function. Similarly, platelet rich plasma has shown to have better outcomes than corticosteroid injections in the management of lateral epicondylitis, and better outcomes than hyaluronic acid injections in the management of osteochondral lesions of the talus. 1.3 Current treatments for degeneration and osteoart