Four-Year Outcomes of Restored Teeth – a Massive Data Analysis

Objectives: Knowledge about outcomes of restorative dental treatment under practice conditions is still sparse. The aim of this study was to evaluate re-interventions after restorative dental treatment under practice conditions using a large insurance database.
Methods: This retrospective study based on claims data from the digital database of a major German national health insurance company. The study was approved by the responsible ethics board. Fee codes and treatment dates allowed for tracing clinical courses. Only teeth of patients who had been members of the insurance company for the whole four-year period 2010 to 2013 were eligible. Kaplan-Meier-survival-analyses were conducted for all teeth after restorative treatment (dental fillings and inlays) except of crowns. Success was defined as not undergoing any restorative re-intervention at the same tooth. Testing for differences among success rates was performed with the Log-Rank-test (P=0.05).
Results: A number of 17,024,344 teeth could be traced after restorative treatment. The cumulative four-year success rates were 69.9% for one surface restorations, 74.8% for two surface restorations, 66.6% for three surface restorations and 61.0% for four surface and more extended restorations. These differences were significant (p<0.0001).
Conclusions: The sustainability of restorative dental treatment under the terms and conditions of the German national health insurance system shows room for improvement. From a public health perspective, special focus should be laid on primary and secondary prevention to minimize the restorative treatment need.