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.