Evaluation of performance of dental providers on posterior restorations: does experience matter? A data envelopment analysis (DEA) approach.

The purpose of this study is to discern what factors affect the longevity of amalgam and of composite restorations by dentists who perform posterior restorations. Data are obtained from the Washington Dental Service and contain 1.5 million patient encounters representing visits to 23,000 providers from January 1993 through 31 December 1999. Analysis of provider performance is estimated through Data Envelopment Analysis. The principal finding is that the most efficient dentists produce posterior restorations that survive almost 5 months (4.6 months) longer than those by inefficient providers (chi2 = 18.98, p < 0.0001). The findings suggest that there is no difference in restoration longevity between amalgam and composite restorations when the restoration is performed by efficient provider.