Temporomandibular joint devices: Treatment factors and outcomes

TMI devices have been used for many years in reconstruction of the temporomandibular joint (TMI). The most common endosseous implant currently used in TMI reconstruction is a mini-anchor that is placed in the posterior head of the condyle to support artificial ligaments to stabilize the articular disk in the proper position. A 2-year follow-up study shows a success rate of 90% in reference to incisal opening, jaw and occlusal stability, and significant reduction in presurgical pain level. Some materials that have been used in TMJ reconstruction, including Proplast-Teflon (PT) and Silastic devices, have caused devastating problems for patients. These materials, (particularly the PT) can cause severe foreign-body giant-cell reaction, severe bone and soft-tissue destruction, and migration of particles to other body areas, and may initiate or exacerbate connective tissue and autoimmune disease problems. Christensen joint prosthesis has been reported to have very good success in TMJ reconstruction. The most thoroughly studied TMI total joint device is the Techmedica custom-made total joint prosthesis, with a 5-year follow-up study on 31 patients and 52 reconstructed joints. All patients have functioning prostheses with good jaw and occlusal stability and an average pain reduction of 4.4 points on a 0-to-10 visual analog pain scale. However, this device currently is unavailable. In complex cases requiring multiple TMI operations, particularly those with previously failed alloplast, a custom-made total joint prosthesis, using materials with proven safety and efficacy in orthopedic joint reconstruction, may be the only option available to improve predictably the quality of life of these patients.