Retrospective clinical evaluation of tapered implants: 10-year follow-up of delayed and immediate placement of maxillary implants

OBJECTIVES: To retrospectively evaluate the clinical outcome of tapered, multithreaded implants (Tapered Screw-Vent MTX; Zimmer Dental, Inc, Carlsbad, CA) with an emphasis on periimplant crestal bone status around those placed delayed and immediately in the posterior and anterior maxilla. METHODS: Chart reviews were performed on 46 patients who had been treated with 173 implants replacing one or more missing and/or unsalvageable teeth in the maxilla. Implant placement and loading was either immediate or delayed. Marginal bone changes were calculated using standardized radiographs taken at implant placement and during annual follow-up. RESULTS: After a mean follow-up of 119 to 121 months, implant survival rate was 99%, and implant success rate was 97%. No discernable bone loss was evident in 85.5% of the surviving implants. Crestal bone loss was observed in 14.5% of all surviving implants: 38.5% of implants immediately loaded and 29.9% of implants with delayed loading. Twenty-one implants exhibited 1 mm of bone loss, 3 implants lost 2 mm, and 1 implant lost 3 mm. Low-density maxillary jawbone and more extensive bone remodeling required around implants immediately placed into extraction sockets were the probable causes of observed bone loss in this study. CONCLUSIONS: Implants exhibited excellent long-term outcomes with little or no bone loss.