Effect of Dentin Conditioning and Bonding Technique on the Shear Bond Strength of an Acetone Based Universal Adhesive

Background: Universal dental bonding systems are able to bond to different dental substrates with different application modes. This study aimed to investigate the effect of different dentin conditioning methods on the dentin shear bond strength (SBS) of an acetone based universal adhesive.Methods and Materials: In this in-vitro study, thirty-five human third molars were collected and sectioned into two mesial and distal halves. Specimens were randomly divided into five groups (n=14). G-Premio Bond (GP) and Clearfil SE Bond (SEB) were used in the experimental and control groups, respectively. Group 1: GP in self-etch mode with dry dentin. Group 2: GP in self-etch mode with wet dentin. Group 3: GP in etch-and-rinse mode with dry dentin. Group 4: GP in etch-and-rinse mode with wet dentin. Group 5 (control group): SEB was applied in self-etch mode. Spectrum composite resin was bonded to the prepared surfaces. SBS was measured using a universal testing machine and the failure mode was determined using a stereomicroscope. Data were analyzed using ANOVA, Tukey’s post-hoc test and Chi-square test.Results: Mean SBS (MPa) per group in descending order was as follows: Group 5 (34.08±10.81), Group 1 (26.58±6.57), Group 2 (24.00±7.04), Group 3 (21.19±8.57) and Group 4 (19.81±6/85). One-way ANOVA revealed that there was a statistically significant difference between the study groups regarding the mean shear bond strength values (P<0.001). According to Tukey’s post-hoc test, groups 2,3 and 4 exhibited significantly lower mean shear bond strength values compared to the control group. There was no significant difference regarding the distribution of different failure modes (P=0.328).Conclusion: SBS of GP in self-etch mode with dry dentin was comparable to that produced when using SEB. Using the etch-and-rinse technique reduced the SBS of GP. Dentin moisture had no negative effect on the SBS of GP when used in self-etch mode.