Forty-one patients received 49 single-tooth implants in different jaw locations. One implant was not osseointegrated at the stage 2 surgery. Three successfully osseointegrated implants were not available for follow-up. Forty-five implants were monitored for 1 to 8 years after loading. Each one of the implants met all of the traditionally accepted success criteria, except for nine individual implants that didi not meet the proposed bone level criterion. No success criteria exist for natural teeth adjacent to implants. Although preliminary results are favorable, extensive long term studies are needed to determine which specifie criteria comprise optimal functional and esthetic results with minimal risk mordibility. (Int J Oral Maxillofac Implants 1996;11:311-321)