Effect of Trichloroacetic Acid on the Bond Strength of Calcium Silicate-Based Cements: A Modified Push-Out Test

Objective: This study aimed to investigate the effect of trichloroacetic acid (TCA) on the bond strength of calcium silicate-based cements to dentin. Methods: Ten single-rooted bovine teeth were sectioned longitudinally into slices 2 mm thick. Six holes were drilled with a 1.2 mm diamond bur in each dentin slice (totally 60 holes). Cotton pellets with TCA were applied to three holes of each slice for 1 min, whereas no acid was applied to the other three. The TCA and non-TCA groups were divided into three subgroups according to the material used: ProRoot mineral trioxide aggregate [(MTA); n=10], Harvard MTA (n=10), and Biodentine (n=10). After seven days, the dislodgement resistance of the materials was calculated using a universal testing machine. The types of bond failure were examined under a stereomicroscope. Results: The TCA had no statistically significant effect on the bonding strength of the tested materials (p>0.05). The Harvard MTA subgroup had the lowest mean bond strength values (2.25±0.79 MPa), while the Biodentine subgroup had the highest (10.49±3.32 MPa). The most common bond failure types were mixed in the ProRoot MTA subgroup (60%) and cohesive in the Harvard MTA (60%) and Biodentine (70%) subgroups. Conclusion: The bond strength of Biodentine is greater than those of ProRoot and Harvard MTA. TCA does not affect the push-out bond strength of MTA or Biodentine.