The purpose of this study was to evaluate the long-term clinical and radiologic effects of a temporary silicone implant after diskectomy of the temporomandibular joint. Forty-three temporomandibular joints in 43 patients with painful disk displacement underwent a diskectomy. A sheet of medical-grade silicone was temporarily placed in 22 patients; 21 patients did not receive an implant. The patients were clinically and radiologically examined 5 years after surgery. On the basis of symptoms and jaw function, they were classified as having good (30 patients), acceptable (8 patients), and bad (5 patients) results. All the patients with bad results and five of the eight patients with acceptable results had received implants. Erosive changes of the condyle or fossa were seen radiographically at follow-up in eight patients, each of whom had received an implant. No positive clinical or radiologic effects of the implants could be identified. The use of a temporary silicone implant after diskectomy of the temporomandibular joint in patients with internal derangement should be seriously questioned.