Cost-minimization Analysis of Post-retained Restorations

Objectives: Survival of post-retained restorations have been studied with few considering an economic evaluation. The aim of this study was to assess four post-retained restorative strategies in endodontically treated teeth using a cost-minimization analysis.
Methods: A cost-minimization analysis was performed based on primary data from a randomized clinical trial and followed the CHEERS guidelines. Four restorative strategies (teeth with ferrule⁺ restored with glass fiber posts and resin composite or crown, teeth without ferrule^- restored with glass fiber post or cast metal post with crown) in 225 teeth in 141 patients were annually evaluated between 2009 and 2018. Initial costs and incremental costs (i.e. maintenance costs per year) were calculated. Survival curves were created by the Kaplan-Meier method followed by log-rank test. Kruskal Wallis followed by Dunn's test were applied in order to compare restorative treatments with a 5% α.
Results: Initial discounted costs were higher for cast metal post with crown^- (US$153.14). The lowest cost was for glass fiber posts with composite⁺ (US$27.11) where the highest number of failures occurred but were mainly restorative fractures and could be repaired. In contrast, glass fiber posts used with crowns⁺ presented a higher number of extractions leading to higher costs. Mean annual cost were significantly lower for the teeth restored with composite⁺ (p<0.001). Ferrule did not significantly impact on annual costs.
Conclusions: Glass fiber posts and direct composite showed significantly lower annual costs than other alternatives involving crowns or metal posts. Additional factors should be considered during clinical decision-making.