Long-term results of the use of silicone sheets after diskectomy in the temporomandibular joint: clinical, radiographic and histopathologic findings

The aim of the present study was to evaluate the long-term results of a gro up of patients who had the disk of the temporomandibular joint (TMJ) remove d and permanently replaced by a silicone sheet. The study group comprised 4 8 patients, treated in the period from 1983 to 1993. In eight patients, the implants had to be removed after an average interval of 5.6 years and they were submitted for histopathological examination. Twenty-five of the 40 pa tients with silastic implants in place, and five of the 8 patients who had their implants removed, were available for long-term follow-up (mean interv al of 7.0 years, SD 2.8 years). Clinical function was rated according to th e Helkimo Dysfunction Index and compared to the preoperative findings. Resu lts showed decreased tenderness of muscles and joints to palpation and incr eased mouth opening, but no statistically significant improvement in joint function. In 4 patients, a decrease in condylar width was found, while anot her 4 patients presented with thickening of the condyle by appositional bon e formation. Histopathology of the failed implants showed scattered fragmen ts of silastic material and dacron fibers with accumulation of histiocytes in immediate contact with the silicone particles and phagocytozed intracell ular material. T-lymphocytes were also present in the vicinity of the silic one particles.