Clinical evaluation of light-cured anterior resin composites over periods of up to 4 years.

Seven hundred light-cured anterior restorations were placed in the permanent teeth of 161 patients by one researcher and evaluated over 4 years. One microfilled and two hybrid resins were assessed for their handling and for gingivitis adjacent to them, surface staining, marginal staining, and color mismatch. Restorative failures were related to the material, patient age, tooth site, and class of preparation. The different handling properties of the three resins did not affect their clinical behavior. There were only 10 unsatisfactory instances from 1626 restoration observations for the four clinical parameters assessed, and no clinically significant differences were found between the three materials, apart from the initial lighter shade mismatches of the microfilled resin. There was no obvious clinical deterioration recorded for most of the restoration observations, although all restorations deteriorated slightly over the study. There were no significant failure differences between the three resins, but significantly more failures occurred in elderly patients, restored (Class V) premolar teeth, and Class IV and V preparations. Of the 43 restoration failures, 81% were from Class V preparations, which reflected undue reliance on a dentin-bonding resin system for restoration retention in premolar cervical abrasion-erosion lesions.