Twenty-six-Year Assessment of Anterior Resin Restorations -Two Restorative Procedures

Objectives: The aim of this randomized clinical study was to compare the long-term quality and longevity of anterior resin restorations completed with two restorative procedures.

Methods: The material consisted of 52 pairs of Class III restorations made in 35 patients in the microfilled resin Silar® using two modifications of the conventional acid-etch restorative procedure: A) bevelling of cavity margin, and B) cavity treatment with a dentin adhesive NPG-GMA in ethanol and re-etching and coating of the finished restorations with low viscous resin. The restorations were examined at baseline and after 2, 4, 6, 11 and 26 years. Information concerning repair and replacement of restorations were collected from the patients' records through their general practitioners. Data were processed by nonparametric statistics for paired observations and Kaplan-Meier survival analyses.

Results: After 26 years were 54 restorations clinically controlled, and 28 restorations were assessed through the dental records. 7 patients had died, and 2 patients did not want to participate in the final folllow-up. 25 A and 21 B restorations had been replaced (p>0.05).

The remaining restorations showed one or more failures, but none of them were in need of replacement. The cumulative survival rates were almost congruent during the whole observation period with a median survival time of 23 years for A restorations and 25 years for B restorations (p>0.05).

Conclusions: The study showed that it was possible to perform Class III restorations with a high clinical quality and a long durability using the materials and methods available in the beginning of the 1980's, and that the restorative procedures had an insignificant influence on the clinical quality and longevity of the restorations.

Support: The restorative materials were provided by the manufacturers.