Shear bond strength evaluation of resin composite bonded to three different liners: TheraCal LC, Biodentine, and resin-modified glass ionomer cement using universal adhesive: An in vitro study

Aims: To compare and evaluate the bonding ability of resin composite (RC) to three different liners: TheraCal LC™ (TLC), a novel resin-modified (RM) calcium silicate cement, Biodentine™ (BD), and resin-modified glass ionomer cement (RMGIC) using an universal silane-containing adhesive and characterizing their failure modes.

Materials and methods: Thirty extracted intact human molars with occlusal cavity (6-mm diameter and 2-mm height) were mounted in acrylic blocks and divided into three groups of 10 samples each based on the liner used as Group A (TLC), Group B (BD), and Group C (RMGIC). Composite post of 3 mm diameter and 3 mm height was then bonded to each sample using universal adhesive. Shear bond strength (SBS) analysis was performed at a cross-head speed of 1 mm/min.

Statistical analysis used: Statistical analysis was performed with one-way analysis of variance (ANOVA) and post hoc test using Statistical Package for the Social Sciences (SPSS) version 20.

Results: No significant difference was observed between group A and group C (P = 0.573) while group B showed the least bond strength values with a highly significant difference (P = 0.000). The modes of failure were predominantly cohesive in Groups A and B (TLC and BD) while RMGIC showed mixed and adhesive failures.

Conclusions: Hence, this present study concludes that the bond strength of composite resin to TLC and RMGIC was similar and significantly higher than that of BD following application of universal adhesive.