Prosthetic Survival and Complication Rate of Single Implant Treatment in the Periodontally Healthy Patient after 16 to 22 Years of Follow-Up.

BACKGROUND: Single implants were introduced in the 1980s, but long-term follow-up is scarce. PURPOSE: The study aims to retrospectively investigate the prosthetic survival and complication rates of single implants in periodontally healthy patients after 16-22 years, and to evaluate the influence of different prosthetic procedures. MATERIALS AND METHODS: Patients with a single implant were recalled for clinical examination. Prosthetic procedures included single-tooth (ST) and CeraOne (CO) abutments supporting a porcelain-fused-to-metal (PFM), all-ceramic (CER), or gold-acrylic (ACR) crown. Prosthetic survival, success, and occurrence of biological, technical, and aesthetic complications were obtained. Procedures were compared by log-rank tests. RESULTS: Fifty patients attended the examination. All implants were functional; however, 15% of abutments and 27% of crowns had been renewed. Replacements (1/4) were related to technical issues whereas the main cause was aesthetics. The abutment cumulative survival rate (CSR) differed significantly between ST-PFM (74%), ST-ACR (0%), and CO reconstructions (97%). The crown CSR was significantly lower for ST-ACR crowns (0%) compared with ST-PFM (68%) and CO (81%). Thirty-nine percent of implants remained complication free throughout the mean 18.5 years. Complications (1/3) required component replacement, and 53% occurred within 5 years after surgery. CONCLUSION: Prosthetic survival rates of single implants are encouraging after 16 to 22 years. However, 66% of the patients encountered at least one complication during follow-up.