The clinical performance of all-ceramic implant-supported single crowns: A systematic review and meta-analysis

Objective: This review aimed at evaluating the survival and technical complication rates of all-ceramic implant-supported single crowns (SC). Material and Methods: Three electronic databases were searched for clinical studies conducted at >= 15 patients examining implant-supported all-ceramic SCs over >= 12 months. Survival rates of implants and restorations plus technical complication rates of SCs were calculated and tested for statistical correlation with confounding variables. Statistical analysis was performed using a negative binomial distribution model to calculate 5- and 10-year survival and complication estimates. Results: Forty-one included studies reported on implant-supported SCs made of veneered and monolithic high-strength oxide ceramics, monolithic, and veneered glass-based ceramics and of a monolithic resin-nano-ceramic (RNC). Survival estimates for SCs of 93% (95% CI: 86.6%-96.4%) after 5 years and 94.4% (95% CI: 91.1%-96.5%) after 10 years were calculated, corresponding values for implant survival were 95.3% (95% CI: 90.6%-97.7%) and 96.2% (95% CI: 95.1%-97.1%). Technical complication rates after 5/10 years were as follows: chipping 9.0% (95% CI: 5.4%-14.8%)/2.7% (95% CI: 2.1%-3.5%), framework fractures 1.9% (95% CI: 0.7%-4.9%)/1.2% (95% CI: 1%-1.5%), screw loosening 3.6% (95% CI: 1.6%-8.4%)/5.2% (95% CI: 3.6%-7.5%), and decementations with 1.1% (95% CI: 0.4%-2.8%) after 5 years. Some confounding variables influenced the above-mentioned estimates significantly. Conclusions: All-ceramic implant-supported SCs showed-with the exception of a RNC material-high survival rates. However, failures and technical complications occurred which have to be considered when informing patients on the treatment with implant-supported all-ceramic SCs.