Marginal fit of class II cavities restored with bulk-fill composites

Abstract

Purpose To evaluate the marginal integrity of three types of bulk-fill composite resins in class II cavities. Materials and methods Simple class II cavities with parallel walls were prepared in 40 extracted human sound molars were selected. The overall dimensions and depth of the cavities were standardized as follow: 4 mm length occlusocervically, 4 mm width buccolingually and 2 mm depth axially. The teeth were randomly divided into four groups (n = 10 each): group 1: Tetric N-Bond Universal and Tetric EvoCeram Bulk Fill composite; group 2: Single Bond Universal and Filtek Bulk Fill posterior composite; group 3: Futurabond U and Admira Fusion X-Tra; group 4: Tetric N-Bond Universal and Tetric EvoCeram composite. All samples were thermocycled for 600 cycles. Impressions of the teeth were made using a polyvinyl siloxane then poured with epoxy resin. These replicas gold sputtered and examined under scanning electron microscopy. Results Group 3 recorded the lowest mean marginal gap length value, while group 4 recorded the highest mean marginal gap length value. One-way analysis of variance was used to compare the tested groups at a level of significance (P ≤ 0.001). For width of proximal gap the lowest mean marginal gap length value found in group 3, while the highest mean value of gap width proximally found in group 1. In width of cervical gap the lowest mean marginal gap length value was found in group 3, while the highest mean value of gap width cervically found in group 4. One-way analysis of variance test was used to compare the tested groups at a level of significance (P ≤ 0.05). Conclusion Admira Fusion X-Tra has good results compared to other used bulk fill and conventional composites.