Evaluation of Microleakage and Microtensile Bond Strength of Two Bulk Fill Composites in Primary Teeth after Caries Removal by Chemomechanical Technique

Abstract

Aim: Evaluation of microleakage and microtensile bond strength of two bulk fill composites (X-tra fill packable and X-tra base flowable bulk fill composites) in primary teeth after chemomechanical caries removal. Material and methods: Forty extracted human primary posterior teeth with caries not involving pulp exposure were assigned after caries removal by Papacarie into two groups according to restorative material used, each containing 20 teeth. Group 1: was restored with X-tra fill. Group 2: was restored with X-tra base. In two groups Futurabond dual-curing self-etch bond was used to bond restorations to the dentin. Both groups were subdivided into two subgroups: Sub-group A: 10 teeth for microleakage test. Sub-group B: 10 teeth for microtensile bond strength test. For microleakage test: After thermocycling; teeth were covered with varnish then immersed in 2% methylene blue for 24 hours, thereafter the dye penetration was assessed with measured in micrometer using MA100 fully configured Halogen inverted scope. For microtensile test: The samples were sectioned longitudinally to the long axis of the tooth to obtain sticks of standardized cross sectional area. These sticks were stressed to failure under tensile force in a universal testing machine. The µTBs for each specimen was calculated in megapascal. Results: X-tra Fill showed lower insignificant mean microleakage compared to X-tra Base at P value =0.3. X-tra Fill showed higher insignificant mean µTBs (MPa) compared to X-tra Base at P value =0.097. Conclusion: Both bulk fill composites have performed approximately similar regarding microleakage and µTBs after using Papacarie in caries removal.