Shear bond strength and microleakage of novel glass-ionomer cements: An In vitro Study

Background: The overall success of dental restorations depends on the materials' ability to bond to dental structures and to eliminate the microleakage. Therefore, the aim of this study was to evaluate the shear bond strength (SBS) and microleakage of novel glass-ionomer restorative materials. Materials and Methods: In this study 62 intact molars were used, of which 30 molars were sectioned buccolingually, embedded in acrylic resin, and polished to obtain flat dentin surfaces. Then, glass-ionomer cylinders were built on the specimens (n = 15) with a high-viscosity glass-ionomer cement (GIC) (EQUIA Fil), a glass-carbomer (Glassfill), a zirconia-reinforced GIC (Zirconomer), or a conventional GIC (RivaSelfCure), and SBS testing was performed. For microleakage test, Class V cavities were prepared on buccal and lingual surfaces of the remaining 32 teeth and divided into four groups (n = 16). Each group was restored with one of four GICs and subjected to microleakage testing. The data were statistically analyzed (P = 0.05). Results: The highest SBS values were observed in Glassfill group (P < 0.05). There were no significant differences on the SBS values of other three materials (P 0.05). Regarding microleakage evaluations, no significant differences were observed at enamel margins (P 0.05), whereas at dentin margins, EQUIA Fil and Zirconomer showed less microleakage than Glassfill (P < 0.05). Conclusions: Although the glass-carbomer restorative materials revealed higher SBS, other tested materials might be more reliable in clinical use, as they offer better leakage resistance.