Microleakage of zirconia frameworks cemented with two types of phosphate monomer-based resin cements

Abstract

Abstract Objective: Resin cements containing phosphoric acid modified methacrylate monomers are commonly used for zirconia-based restorations. However, there are few studies of microleakage of zirconia frameworks cemented with these types of resin cements. The purpose of this study was to compare microleakage of zirconia frameworks cemented with two types of phosphate monomer-based resin cements after long-term thermocycling. Materials and Methods: Totally, 30 permanent premolars were randomly divided into two groups: Self-etching (SE) (Panavia™ F2.0, Kuraray Medical, Japan) and self-adhesive (SA) (RelyX™ U100, 3M ESPE, USA) resin cements. The teeth were prepared for zirconia frameworks, which were fabricated by TDS CAD/CAM. After cementation and thermocycling (20,000 cycles), specimens were immersed in 2% methylene blue dye solution for 24 h and were sectioned mesiodistally and buccolingually. Microleakage was recorded, and the data were analyzed using the Mann-Whitney U-test and Sign test (α = 0.05). Results: All specimens showed significantly higher microleakage scores at the cementum margins than at the enamel margins (P < 0.05). The SE resin cement provided significantly lower microleakage scores than the SA resin cement at the enamel margin (P < 0.05); however, there were no statistically significant differences in microleakage between two resin cements at the cementum margins (P > 0.05). Conclusion: SE resin cement has a better sealing ability than SA resin cement at the enamel surface. Both resin cements presented high microleakage at the cementum margins, especially at the tooth/resin interface.