A systematic review of the survival and complication rates of fixed partial dentures (FPDs) after an observation period of at least 5 years IV. Cantilever or extension FPDs

Objectives: The objective of this systematic review was to assess the survival of cantilever fixed partial dentures (FPDs) and the incidence of biological and technical complications. Methods: An electronic MEDLINE search supplemented by manual searching was conducted to identify prospective and retrospective cohort studies on FPDs with a mean follow-up time of at least 5 years. Patients had to have been examined clinically at the follow-up visit. Assessment of the identified studies and data abstraction was performed independently by two reviewers. Failure and complication rates were analyzed using random-effects Poisson regression to obtain summary estimates of 10-year survival proportions. Results: From a yield of 3658 titles and 211 abstracts, 81 articles were selected for full-text analysis, finally resulting in 13 studies that met the inclusion criteria. Meta-analysis of these studies resulted in an estimated survival rate of cantilever FPDs of 81.8% (95 percent confidence interval (95% CI): 78.2-84.9%) and success rate (free of all complications) of 63% (95% CI: 54.7-70.2%) after 10 years. The most common biological complication was loss of pulp vitality (32.6%) followed by caries at abutment teeth (9.1%). After a 10-year observation period 2.6% of the FPDs were lost as a result of dental caries and 1% due to recurrent periodontitis. The most frequent technical complication was loss of retention (16.1%) followed by material fractures (5.9%). The cumulative incidence of fractures of abutment teeth was 2.9% and 2.4% of the FPDs were lost as a result of abutment tooth fracture after an observation period of 10 years. Conclusion: This systematic review on cantilever fixed partial dentures indicated that survival and success rates of cantilever fixed partial dentures were lower than those of conventional end-abutment supported FPDs described in a review by Tan et al. (2004) and biological and technical complications were frequent.