Comparing the Effect of Different Dentin Conditioners on the Microshear Bond Strength of High Viscosity Glass Ionomer Cements to Dentin

Abstract

Background: This study aimed to evaluate the influence of using tannic acid 20% (TA) and polyacrylic acid (PAA) as dentin conditioning agents on the microshear bond strength (µSBS) of two types of high viscosity glass ionomer cements (HVGICs).Materials and Methods: This in vitro study was conducted on 60 extracted human premolars. The occlusal enamel was removed using a high-speed handpiece under water-cooling in order to expose the dentin. A sectioning device was used to create a flat surface of superficial dentin. Samples were randomly divided into two groups (n=30) based on the type of HVGIS used: Fuji II LC CAPSULE or Equia Forte glass ionomers. The samples of each group were randomly divided into three subgroups (n=10) based on the type of surface conditioning received. Prior to applying the glass ionomer cements, the dentine was conditioned with either PAA, TA or a combination of PAA and TA. A universal testing machine was used to measure the µSBS of each specimen and was recorded in MPa. The mode of failure was evaluated with a stereomicroscope at ×40. Two-way ANOVA and Tukey post-hoc tests were employed to conduct comparisons between different groups. P-value<0.05 was considered statistically significant.Results: Two-way ANOVA revealed that there was a significant interaction between the type of utilized HVGIC and the dentin conditioning agent (P< 0.001). Pairwise comparison with Tukey’s post-hoc test showed that the differences between the µSBS values of different groups was always statistically significant, except for the difference between groups Fuji + TA and Equia + PAA (P=0.155), and also Equia + TA and Equia + PAA + TA (P=0.09).Conclusion: Applying polyacrylic acid as a dentin conditioner showed superior results compared to tannic acid in terms of µSBS values and improving the dentin bond performance of the tested HVGICs.

Keywords

• glass ionomer cements
• tannic acid
• microshear bond strength