Three-year clinical evaluation of a polyacid-modified resin composite in minimally-invasive occlusal cavities

Objective: The aim of this study was to evaluate the 3-year clinical perfor mance of one polyacid-modified resin composite material (PMRC), Dyract, in minimally invasive occlusal cavities and its neighbouring fissures. Method: One hundred and sixteen restorations of the material investigated w ere placed by a single operator in a group of selected children under contr olled conditions. Isolation of the restorations was accomplished with the u se of cotton rolls and aspiration. Using modified US Public Health Service (USPHS) codes and criteria, the restorations were reviewed clinically withi n 1 week of placement (baseline), and thereafter at 6 months, 1, 2 and 3 ye ars. Results: After 3 years, marginal discolouration was present in 8.6% of the restorations. The marginal adaptation was rated as partly sealed (Oscar-Alp ha) in 107 (92.2) of the restorations. Five restorations had lost their sea lant components, while four restorations were partly sealed with explorer-c atch after 3 years. Although wear of the restorations was considerable, res torations rated as 'partly sealed' had at least two-thirds of their sealant components fully retained. Recurrent caries was associated with four (3.4% ) restorations. Conclusion: In this clinical study, the retention rate of the tested PMRC m aterial was good, although a marked occlusal wear was evident. The marginal adaptation of the PMRC at the enamel site would probably have been better by the use of enamel-etching. Provided the marginal adaptation and wear res istance of the material is further improved, clinical use of PMRCs in minim ally invasive occlusal cavities can be advocated. (C) 2000 Elsevier Science Ltd. All rights reserved.