An Up-to-15-Year Comparison of the Survival and Complication Burden of Three-Unit Tooth-Supported Fixed Dental Prostheses and Implant-Supported Single Crowns

Purpose: To assess and compare the outcomes and economic complication burden of three-unit toothsupported fixed dental prostheses (TFDPs) and implant-supported single crowns (ISCs) provided to a sequential cohort in a specialist prosthodontic practice over a 15-year period. Materials and Methods: Sequential patients requiring replacement of a single missing tooth between 1996 and 2010 with a metal-ceramic three-unit TFDP (n = 145 patients, n = 174 prostheses) or ISC (n = 174 patients, n = 220 prostheses) were included. Prostheses subjectively judged at insertion to have an unfavorable 10-year prognosis (17 TFDPs, 0 ISCs) were removed from statistical analyses. The estimated cumulative survival (ECS) was calculated with the life table actuarial method and standard errors calculated with the Greenwood formula. Differences in outcomes between all prostheses and those replacing only anterior or only posterior teeth were assessed with the log rank test. Complication incidence, severity, and economic burden, measured in time/cost accounting units (TAUs), were tallied and compared descriptively. Results: The 15-year ECS did not differ for 112 TFDPs (92.75% ± 3.28%) and 81 ISCs (95.95% ± 2.92%) replacing posterior teeth. However, the 15-year ECS was significantly greater for 139 ISCs (93.33% ± 6.44%) than for 45 TFDPs (82.82% ± 6.50%) replacing anterior teeth. The economic burden of nonterminal complications for both prostheses was low (mean = 0.3 and 0.2 TAUs per prosthesis for TFDPs and ISCs, respectively). This equated to 3 TAUs/100 years in clinical service and 4 TAUs/100 years in clinical service for the TFDPs and ISCs, respectively. Conclusion: The survival of three-unit TFDPs and ISCs over 15 years was not statistically different when replacing posterior teeth, but ISCs survived significantly better when replacing anterior teeth. The complication rates of the TFDPs and ISCs were similar, but the economic burden for the TFDPs was greater. Keywords: cost analysis, fixed dental prostheses, implant-supported single crowns, prospective study, survival analysis