Purpose: The purpose of this study was to examine retrospectively the outcome of wide-diameter dental implants used to retain fixed restorations in the posterior segments of the maxilla and mandible. Materials and Methods: Fifty-two patients were consecutively treated between 1997 and 2000 with 78 Wide-Platform (WP) Mk II implants in the posterior regions of the maxilla and/or mandible. All treated patients were called for a retrospective examination between September and November 2001. At the examination, data regarding general health and clinical and radiographic parameters were collected according to a strict protocol. Thirty-four women and 18 men with a mean age of 55 years (range 19 to 81 years) participated. Twenty-three WP implants were placed in the maxilla and 55 in the mandible. The mean time in situ was 33 months (range of 11 to 58 months). Results: Of 78 implants, 8 had been lost by the time of reexamination. Five women lost 1 implant each in the maxilla, and 2 men lost 3 implants in the mandible. The survival rate was 89.8%. Discussion: The results are encouraging because the WP implants were placed in rather unfavorable situations (generally poor bone quality, compromised bone volume, and larger occlusal forces). Conclusion: Based on the reported survival rate, wide-diameter implants present an acceptable treatment alternative.