Long-term treatment costs and cost-effectiveness of restoration repair versus replacement.

OBJECTIVES: When managing partially defective restorations, dentists can choose between repair and replacement. We aimed to assess the long-term treatment costs of repairs and replacements. METHODS: Partially defective anterior and posterior composite restorations in permanent teeth had been repaired or replaced in a German university hospital and were retrospectively followed until censoring or one of the following events: (1) Extraction, (2) Major complications including placement of indirect restorations, endodontic treatments and extractions, or (3) Any complications including major complications and further direct restorations. Costs were estimated from a German mixed public-private-payer perspective. Cost-effectiveness differences were described using median-based incremental-cost-effectiveness ratios (ICER(MEDIAN)). Statistical analysis was performed using generalized linear mixed modeling (GLM), Chi(2)-test, and Wilcoxon rank-sum test (p < 0.05). RESULTS: A total of 616 repairs in 468 patients (follow-up: 4.9 +/- 4.1 years) and 264 replacements in 218 patients (follow-up: 4.8 +/- 4.3) were included. While replacements were associated with higher initial treatment costs, median annualized treatment costs did not significantly differ between repair (47.58 Euro [IQR: 24.41-107.04]) and replacement (50.64 Euro [IQR: 26.30-118.78]; p > 0.05), but were higher for molars (75.53 Euro [IQR: 24.41-92.18]) than incisors (45.03 Euro [IQR: 28.19-168.50]; p = 0.011). The difference in the % of extractions, major and any complications were minimal between both groups. The mean ICER(MEDIAN) of replacement vs. repair was -146.8 Euro/% when extractions were considered as outcomes. Regarding major and any complications, mean ICER(MEDIAN) amounted to 67.6 Euro/% and 23.9 Euro/%, respectively. SIGNIFICANCE: Repairs and replacements of partially defective restorations showed similar long-term costs and cost-effectiveness.