Effect of finishing method on the microleakage of Class V resin composite restorations

Purpose: To evaluate the effect of three finishing methods on the microleakage of Class V hybrid resin composite. Materials and Methods: Facial and lingual Class V cavities were prepared at the cemento-enamel junction of bovine incisors. Restorations of the two materials (Z100; Prodigy) were placed, using the supplied dentin-adhesives (Scotchbond Multipurpose; OptiBond FL, respectively). Finishing methods were carbide (C) and diamond (D) finishing instruments operated at high-speed, and finishing disks (S). After thermal cycling, the teeth were immersed in methylene blue dye, then sections of the restored teeth (n=12) were visually assessed for leakage. Results: No leakage was observed at the resin-enamel interface in any restoration. At gingival margins, the incidence of leakage (slight/severe) was: Z100 D = 4/3, C = 5/3, S = 2/0; Prodigy D = 3/0, C = 2/4, S = 3/2. The greatest incidence of leakage was observed in restorations finished with carbide finishing burs. A two-way ANOVA of leakage data rankings showed no significant difference among the three methods (P= 0.07) or between the two materials (P= 0.55), and no significant interaction of material and finishing method (P= 0.07).