Performance of fixed dental prostheses up to 6 years—A massive data analysis

Abstract

Statement of problemMetal and metal-ceramic fixed dental prostheses (FDPs) have been clinically determined to provide long-term durable restorations. However, data on their performance under practice conditions are sparse. PurposeThe purpose of this clinical study was to evaluate the longevity of FDPs under practice conditions by analyzing a large insurance claims database. Material and methodsData were extracted from the data warehouse of a major German national health insurance company (BARMER). The analysis focused on the FDP types with the lowest deductibles in the insurance system. All metal-based FDPs replacing up to 3 adjacent teeth were included. Ceramic veneering was optional and only approved on the labial surfaces of maxillary teeth mesial to the first molar and mandibular teeth mesial to the second premolar. Fee codes allowed clinical courses to be traced on a day count basis. Three groups with FDPs replacing 1 tooth, 2 teeth, and 3 teeth were formed. Kaplan-Meier survival analyses were conducted for the target events removal or extraction, indicating FDP failure and extraction of an abutment tooth. ResultsThe sample comprised 124 660 FDPs that replaced 1 tooth (76.5%), 2 teeth (19.8%), or 3 teeth (3.7%). The cumulative survival rates for removal or extraction at 6 years differed significantly, with 83.0% for 1-pontic FDPs, 78.1% for 2-pontic FDPs, and 74.0% for 3-pontic FDPs. Thus, approximately 1 of 6 one-pontic FDPs, 1 of 5 two-pontic FDPs, and 1 of 4 three-pontic FDPs failed. The cumulative survival rates for extraction of an abutment tooth at 6 years showed no significant difference, with 96.0% for 1-pontic FDPs, 95.6% for 2-pontic FDPs, and 95.1% for 3-pontic FDPs. ConclusionsThe survival rates of FDPs according to insurance data were lower than those reported by clinical studies, indicating a gap between efficacy and effectiveness.