“Comparative Evaluation of Microleakage in Zirconia Crowns Cemented With Bioactive, Conventional Gic and Dual Cure Resin Luting Cements - An in Vitro Study”

Purpose: The objective of this study was to evaluate and compare the microleakage in Zirconia crowns cemented with Bioactive, Conventional GIC, and Dual Cure Resin Luting Cements. Materials and Methods: 45 Freshly extracted permanent molars were randomly equally divided. Group 1- Bioactive Cement, Group 2: Conventional GIC and Group 3: Dual Cure Resin Cement. Teeth were embedded in resin blocks 1 mm cervical to CEJ and prepared according to the standardized protocols, zirconia crowns were fabricated using CAD CAM technology and cemented onto the respective tooth preparations according to the manufactures instructions and excess cement was removed. After cementation all restored teeth were placed in buffered saline solution at 37 degrees centigrade for 1 day. Samples of each group were divided into 3 subgroups i.e. A, B and C, (5 samples each) and for aging subgroup B and C of all groups were placed in a thermocycler for 6000 and 10,000 cycles alternating between 5 degrees centigrade and 55 degrees centigrade to simulate aging at 6 months and 12 months respectively. All samples were painted with acrylic varnish to within 1 mm of crown margin and were placed in 2 % basic fuchsin dye solution. After 24 hrs. they were sectioned buccolingually, and were examined under a stereomicroscope at 30 X magnification for microleakage and scored. Results: Based on results obtained by statistical analysis of the readings recorded from stereomicroscope for microleakage it was concluded that the microleakage score of group 1 samples was significantly less than that of samples in group 2 (p value-0.001*) and in group 3 (p value-0.007*). There was no significant difference in the microleakage score of groups 2 and 3 samples (p value-0.061). Conclusions: The research revealed that the Bioactive luting agent exhibited lower microleakage than Conventional GIC, and Dual Cure Resin Luting Cement. Therefore, the null hypothesis was rejected.