Effects of enamel-bonding, type of restoration, patient age and operator on the longevity of an anterior composite resin.

This study examined the survival of an anterior composite resin placed with or without enamel acid-etching using a low viscosity enamel bonding resin, for periods of approximately 16 years. The 950 conventional composite resin restorations were placed by numerous students and dentists for patients attending a dental hospital. Restorative failures were assessed using the life table method and specifically evaluated the placement method, type of restoration, patient age, and the dentist. There were no significant statistical differences between the two placement methods, or the two university and hospital dentist groups. However, there were significantly more failures with the Class IV restorations and in the oldest patient group. The enamel acid-etching and an enamel bonding resin did not display an advantage over unetched cavity preparations. The median survival for both methods of composite resin placement was 8-9 years.