Long-term Study Using TPS-SteriOss¨? Implants in Partially Edentulous Patients

Long-term Study Using TPS-SteriOss¨? Implants in Partially Edentulous Patients
M. VOGELER, U. HELD, T. GERDS, and J.R. STRUB, Albert-Ludwigs-University, Freiburg im Breisgau, Germany
March 2004
Clinical Implant Studies
Objective: The purpose of this prospective study was to evaluate the success rates of TPS-SteriOss¨? implants. Methods: Two-hundred and sixty-two two-stage TPS-SteriOss¨? implants were placed in 82 partial edentulous patients. Radiographic evaluation started at the insertion of the fixed partial dentures (FPD) and was repeated annually. The Kaplan-Meier estimator was used for success rates. Failure time was recorded when bone resorption exceeded 1.5 mm in the first year or 0.2 mm in subsequent evaluations (Albrektsson et al. 1988, Smith & Zarb 1989). A linear-mixed effects model (Pinheiro & Bates 2000) was used to evaluate the effect of covariates on progression of the periimplant bone resorption. Results: Two-hundred eleven implants, placed in 61 patients (female:39, male:32), restored with 3 single-, 48 splinted- (2 units) and 37 splinted (3 units) ceramic-metal crowns, were clinically evaluated after a mean observation period of 60 months. The drop-out rate was 25.6%. Six implants were explanted before placement of FPD. These implants were omitted from the analysis of success rates and bone resorption. The implant survival rate was 97% after 5 years. After 4 (5) years the estimated implant success rate was 56% (12%) for implants in the maxilla and 57% (30%) for implants in the mandible. The linear mixed effects model showed that implants in the maxilla had a significantly higher bone resorption than implants in the mandible (estimated effect:-0.71, p-value:0.039). Conclusion: TPS-SteriOss¨? implants failed the success criteria by Albrektsson & Zarb. The analysis of bone resorption with the criteria of Albrektsson & Zarb had a significant higher sensitivity than the implant survival analysis. This study was supported by SteriOss¨? (Yorba Linda, CA, USA)