Avaliação retrospectiva de próteses implantosuportadas à base de Zircônia obtidas por sistema CAD/CAM

Abstract

Objectives: The aim of this retrospective study was to evaluate the survival rate and the influence of technical, biological and occlusal factors at implantsupported zirconia restorations obtained by CAD/CAM system. Methods: Two experience prosthodontics researchers working in pairs analyzed and rated all patients. The patients were evaluated according to the characteristics of the restorations; occlusal evaluation; biological evaluation; technical evaluation; radiographic evaluation and the satisfaction index with the treatment. The Kaplan-Meier test was used to estimate the survival rate from the prosthesis survival data. Results: A total of 32 patients and 90 implant-supported zirconia restorations obtained by CAD/CAM system were evaluated, after a mean observation period of 33.045.7 months. The Kaplan Meier survival rate was 90.9% for single, 84.9% for FPD restorations and 100% for complete-arch implant-supported restorations. The most common complications were screw loosening, lack of marginal adaptation and framework fracture. The overall patients’ satisfaction with the treatment was 8.1 (±2,1). Conclusion: The evaluated treatment is an adequate option to metal-free prostheses, however the excessive index of screw loosening, lack of marginal adaptation as well as border fractures, especially in the non-segmented prostheses, shows that improvements must be made in order to minimize the problems encountered