Seventeen oral cancer patients (47 to 78 years, mean 67) were treated with external radiation in areas that included future implant sites. Implants were placed in the irradiated jaws after a period of 18 to 228 months (mean 88 months). The patients received 103 implants and were followed to 1 to 62 months (mean 21 months) after implant loading. The cumulative survival rate of the implants after 1 year was 97% in the mandible and 92% in the maxilla. While the irradiation dose used did not affect implant survival, this result may possibly be influenced by th e addition of hyperbaric oxygen treatment for patients receiving more than 50 Gy. Irradiation for treatment of oral cancer does not seem to reduce the survival rate of implants as compared to those placed in the nonirradiated jaw.