Clinical study on the success of posterior monolithic zirconia crowns and fixed dental prostheses: preliminary report

Abstract

Objective: The purpose of this report was to present preliminary clinical results regarding the success rates and technical outcomes of posterior monolithic zirconia single tooth crowns (STs) and fixed dental prostheses (FDPs). Materials and Method: Thirty-four patients received 43 posterior monolithic zirconia restorations as single tooth crowns (STs) and/or fixed dental prostheses (FDPs), which were fabricated using a CAD-CAM (Computer Aided Design - Computer Aided Manufacturing) system. At baseline and every 6 months, the restorations were examined for survival and technical outcomes. Success of the restorations was defined as the restoration remaining in situ, with no need for removal or replacement at follow-up visits. Technical outcomes were evaluated with a modified version of the United States Public Health Services criteria. Survival of restorations was estimated by using the Kaplan-Meier survival analysis. For each restoration, duration of follow-up was calculated from the time of placement to the date of its first failure. Results: After a mean observation period of 18.6 ± 3.9 months (between 8-24 months), cumulative survival rates were 86.7% and 92.3% for STs and FDPs, respectively. Technical evaluation revealed good marginal adaptation and crown contours; however, modifications were needed for shade and occlusion of restorations. Conclusion: These preliminary results revealed high survival rate and generally successful technical outcomes for posterior monolithic zirconia STs and FDPs.

Keywords

• CAD-CAM
• survival analysis
• yttria stabilized tetragonal zirconia