Long-Term Survival and Peri-Implant Health of Titanium Implants with Zirconia Abutments: A Systematic Review and Meta-Analysis.

To evaluate the long-term implant survival rate of titanium implants with zirconia abutments, and the effects of implants with zirconia abutments on marginal bone loss (MBL) and pocket probing depth (PPD) compared with all-titanium implants. The searched electronic database included the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and the Chinese Biomedical Literature Database. Two types of studies were included: clinical studies reporting the survival rate of titanium implants with zirconia abutments with at least a mean/median 5-year follow-up, and clinical trials reporting the effects of implants with zirconia abutments on MBL and PPD compared with all-titanium implants. Two reviewers screened and selected the records, assessed quality, and extracted data of included studies independently. This review included 16 studies from 18 publications. None of the comparative studies was assessed at a low risk of bias. The overall implant survival rate of implants with zirconia abutments was estimated to be 96% (confidence intervals [CIs] [94%, 98%], I2 = 0%). For the comparison between implants with zirconia abutments and all-titanium implants, the results significantly favored implants with zirconia abutments (for MBL, mean difference [MD] = -0.09, CIs [-0.17, 0.00], p = 0.05, I2 = 40%; for PPD, MD = -0.18, CIs [-0.32, -0.05], p = 0.008, I2 = 0%). Zirconia abutments were favored more when the prosthesis was an implant-supported overdenture rather than a single crown. Implants with zirconia abutments may have an acceptable performance on peri-implant health compared with all-titanium implants; however, the implant survival rate of implants with zirconia abutments is slightly lower than all-titanium implants in the long-term follow-up. Additional studies are needed to explain this dichotomy.