Purpose: Solid one-piece standard and conical abutments, which do not involve the external implant hex when seated, have been designed. The present clinical study represents a 1-year follow-up of the use of these abutments for anchorage of implant-supported fixed prostheses for oral rehabilitation of 36 completely and eight partially edentulous patients. Materials and Methods: After 1 year of loading, the implant-supported dentures were removed, and the seating of the 214 one-piece abutments was inspected clinically and radiographically. Results: After 1 year of loading, no loose abutments were observed. One complication was reported; it involved fracture of two abutment screws within the same fixed denture. Prosthesis mobility and gold screw loosening accompanied this complication. Ninety-one percent of the patients exhibited healthy gingiva, and 9% showed erythema/edema. No periimplantitis was identified. Conclusion: The results of this study--healthy marginal tissue, a mean bone loss of 0.3 ± 0.6 mm, and no abutment retightening 1 year after loading--support the use of the one-piece abutment design in implant-supported screw-retained restorations. Int J Prosthodont 2001;14:159–163.