Taxas de falha e sobrevida em restaurações cerâmicas multilayers CAD-CAM sobre implante fusionadas com nano-fluoropatita: estudo transversal

Abstract

Objective: The aim of this study was to clinically evaluate the failure and survival rates of implant supported screw-retained multilayer ceramics, made with CAD-CAM technology, with zirconia infrastructure and lithium disilicate superstructure, using nano-fluoropatite as a fusion ceramic. Materials and Methods: This study was carried out on a private clinic in Marília – SP, Brazil. All the eligible patients have had received implant supported screw-retained multilayer ceramics, with CAD-CAM zirconia infrastructure and lithium disilicate superstructure, fused with nano-fluoropatite. To determine the failure and survival rates, clinical evaluations were performed, classifying the ceramic restorations as: "Type 1a: Non-critical flaw inside the veneering ceramic", “Type 1b: Critical fissure in the veneering ceramic”, "Type 2a: Non-critical chipping”, “Type 2b: Critical chipping", "Type 3: Chipping of the veneering ceramic with Zirconia core exposure" or "Type 4: Fracture of the Zirconia core" according to the presence of chippings or delaminations. In addition, peri-implant evaluations were performed using Scores 0, 1, 2 or 3 to classify the Index of Gingival Bleeding (mBI) and Index of plaque accumulation (mPI). The Kaplan-Meier test was used to estimate the survival rate from the ceramic and restoration systems. Results: A total of 17 prostheses (6 multiple splinted and 11 single ones) were evaluated, from 6 to 66 months of follow-up. All patients (100%) were satisfied or very satisfied with the prostheses (mean of 9.4 on the graduated scale). All the prostheses (100%) presented no failures, both in infrastructures and superstructures. The following figures were observed for the mBI: 7 prostheses presented Score 0 (41.17%); 3 Score 1 (17.64%); 6 Score 2 (35.29%); and only 1 Score 3 (5.88%). For mPI, 6 prostheses Score 0 (35.29%) were observed; 9 prostheses Score 1 (52.94%); no prosthesis Score 2 (0%); and 2 prostheses Score 3 (11.76%). Only 1 of the prostheses presented significant complications, resulting from a periimplantitis. The Kaplan-Meier survival rate was 100% for the ceramic system and 85% for the restorarion system. Conclusion: This cross-sectional study presented absence of failures and, consequently, high survival rate in the new nano-fluoropatite fusion method in zirconia- based multilayer CAD-CAM restoration, and CAD_CAM lithium disilicate superstructure.