Comparison of Shear Bond Strength of Different Restorative Materials to Tricalcium Silicate-Based Pulp Capping Materials

The aim of this study was to evaluate the shear bond strength (SBS) of three typical restorative materials glass ionomer cement (GIC), resin-modified glass ionomer (RMGIC) and composite resin (CR) to different pulp capping materials, i.e., Theracal LCTM (TLC), BiodentineTM (BD), and ProRootTM white MTA (WMTA). 90 acrylic blocks with a center hole were prepared. The holes were completely filled with three pulp capping materials (TLC, BD, and WMTA), with 30 specimens per capping material. The samples were then randomly divided into 3 subgroups of 10 specimens each and were overlaid with GIC, RMGIC, or CR. A total 9 specimen groups were prepared. The SBS was assessed using a universal testing machine. Kruskal-Wallis test and Mann-Whitney’s test were performed to compare the SBS among the subgroups (p < 0.05). After the SBS test, the fractured surfaces were examined under a stereomicroscope at a magnification of 25×. The highest and lowest SBS values were recorded for TLC-CR and TLC-GIC, respectively. With regard to the SBS to the three pulp capping materials, CR was found to be superior to RMGIC and GIC. BD showed a higher SBS compared to TLC and WMTA when used with GIC.