Comparative evaluation of shear bond strength of universal composite with three different liners: an in-vitro study

Aim

The study was intended to compare the shear bond strength (SBS) of universal composite with three different liners and two different adhesive systems.

Materials And Methods

Sixty maxillary premolar teeth with 3mm diameter and 2 mm depth cavities were prepared and categorized into 3 groups of twenty each. Each group was filled with the respective liners Group I: Biodentine; Group II: Resin Modified Glass Ionomer Cement (RMGIC); Group III: Mineral trioxide aggregate (MTA). Each group had two subgroups according to the adhesive system used: Group A (Prime & Bond, universal adhesive) and Group B (Te-Econom Bonding agent). A split teflon mould was used to build a composite resin of dimensions 2 mm in diameter and 4 mm in depth, and light-cured. The SBS was determined by utilising a knife-edge blade in a universal testing machine, and fractured surfaces were evaluated under a scanning electron microscope.

Results

The findings revealed that RMGIC achieved adequate SBS to universal composite and showed a mixed mode of failure compared to other groups. Applying a self-etch adhesive (Prime & Bond) between RMGIC and universal composite resin significantly enhances SBS as opposed to a total-etch adhesive (Te-ECONOM). Whereas Biodentine and MTA exhibited lower SBS when immediately bonded to the universal composite.

Conclusions

Based on the findings of this study, RMGIC is established as an optimal material for indirect pulp capping in clinical practice, and Biodentine and MTA are ideal for vital pulp therapy in cases of pulp exposure, with Biodentine yielding superior results.