Microleakage of Class-V Inlays using an Experimental Self-Adhesive Resin Cement

Objectives: To evaluate microleakage at coronal and cervical margins of class-V composite inlays luted with a newly developed self-adhesive resin cement in comparison with three other cements.

Methods: An experimental automix self-adhesive resin cement; SAC-A by Kuraray Medical and three self-adhesive resin cements; RelyX Unicem by 3M ESPE, Maxcem by Kerr and Multilink Sprint by Ivoclar Vivadent were used. Twenty Class-V cavities with coronal margins on enamel and cervical margins on cementum were prepared on labial surfaces of bovine incisors and divided into four groups. Inlays were indirectly fabricated with Estenia C&B hybrid ceramic and sandblasted. The inlays were luted using one of the cements and placed in the cavities of each group. Halogen light-cure was used to polymerize the cements. After 24h storage in 37°C water, specimens were thermocycled between 5°C and 55°C for 3500 cycles, sealed, immersed in 0.5% Methylene Blue for 6 hours and then axially halved. Coronal and cervical marginal microleakage scores were determined on each half using a seven-category criterion.(n=10) The statistical comparison was performed between materials using Kuruskal-Wallis, and within materials using Wilcoxon signed-rank tests. (p<0.05)

Results: A degree of microleakage was observed for all cements except for SAC-A, which achieved perfect sealing at both margins. Multilink Sprint showed the highest leakage scores. While there were no significant differences between SAC-A and Unicem, they showed significantly better coronal margin sealing than Maxcem and Multilink Sprint. At the cervical margin, SAC-A, Unicem and Maxcem showed significantly lower leakage than Multilink Sprint. SAC-A exhibited better cervical sealing than Maxcem. No significant difference was found between coronal and cervical margins within each material.

Conclusions: There was a great variability between the tested self-adhesive resin cements. The new experimental self-adhesive resin cement, SAC-A demonstrated excellent results; which were significantly better than other self-adhesive resin cements except Unicem.