A systematic review and meta-analysis on the clinical outcome of zirconia implant-restoration complex

Purpose: This systematic review evaluates the clinical outcome of zirconia implant-associated survival and success rates, marginal bone loss, and implant-restoration complex integrity. Study selection: Using the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines, studies including >= 10 patients restored with zirconia implants supporting single crowns (SCs) or fixed dental prostheses (FDPs) prior to January 2017 were identified. Primary outcomes were survival rates and marginal bone loss around one and two-piece zirconia implants and the associated implant-restoration complex integrity. Results: 1349 studies were selected; after duplicate removal and title screening, 36 remained for full-text screening. 17 studies met the inclusion criteria: 2 randomized controlled clinical studies, 11 prospective clinical studies and 4 retrospective studies. In total, 1704 implants from 1002 patients were evaluated, including 1521 one-piece and 183 two-piece zirconia implants with follow-up between 1 and 7 years. The mean survival rate was 95 % (95 % CI 91-97 %). The overall mean marginal bone loss was 0.98 mm (95 % CI 0.79-1.18); the mean marginal bone loss after 1 year was 0.89 mm (95 % CI 0.60-1.18). No meta-analysis regarding prosthetic outcomes was possible. Conclusions: Survival and marginal bone loss values after one year for one-piece zirconia implants are acceptable, but long-term studies are required to support their clinical use. No particular restoration material can be recommended; this decision is apparently based on clinicians' preferences. Results from two-piece implants do not provide sufficient data to support their clinical use and no abutment or cementing materials for two-piece zirconia implants can be recommended. (c) 2018 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.