Effect of Resin Coating and Chlorhexidine on Microleakage of Two Resin Cements after Storage

Evaluating the effect of resin coating and chlorhexidine on microleakage oftwo resin cements after water storage.Materials and Methods: Standardized class V cavities were prepared on facial and lingualsurfaces of one hundred twenty intact human molars with gingival margins placed 1mm below the cemento-enamel junction. Indirect composite inlays were fabricated and thespecimens were randomly assigned into 6 groups. In Groups 1 to 4, inlays were cementedwith Panavia F2.0 cement. G1: according to the manufacturer's instruction. G2: with lightcured resin on the ED primer. G3: chlorhexidine application before priming. G4: withchlorhexidine application before priming and light cured resin on primer. G5: inlays werecemented with Nexus 2 resin cement. G6: chlorhexidine application after etching. Eachgroup was divided into two subgroups based on the 24-hour and 6-month water storagetime. After preparation for microleakage test, the teeth were sectioned and evaluated atboth margins under a 20× stereomicroscope. Dye penetration was scored using 0-3 criteria.The data was analyzed using Kruskal-Wallis and complementary Dunn tests.Results: There was significantly less leakage in G2 and G4 than the Panavia F2.0 controlgroup at gingival margins after 6 months (P<0.05). There was no significant differences inleakage between G1 and G3 at both margins after 24 hours and 6 months storage. After 6months, G6 revealed significantly less leakage than G5 at gingival margins (P=0.033). Ingeneral, gingival margins showed more leakage than occlusal margins.Conclusion: Additionally, resin coating in self-etch (Panavia F2.0) and chlorhexidine applicationin etch-rinse (Nexus) resin cement reduced microleakage at gingival margins afterstorage.