Effect of Grape Seed Extract on the Microtensile Bond Strengthof NaOCl-treated Dentin
Objective: To evaluate the effect of proanthocyanidin (PA) in grape seed extract on the microtensile bond strength between a two-step self-etch adhesive and sodium hypochlorite-treated dentin.
Methods: Twenty-five flat, ground, coronal dentin specimens were divided into five groups. The dentin surfaces were treated as follows: Group 1, treated with 5.25% NaOCl for 30 seconds; Groups 2-5, treated with 5.25% NaOCl for 30 seconds followed by 5, 10 or 15% PA for 30 seconds, respectively; and Group 5, no treatment (control group). After rinsing with distrilled water for 10 seconds and air-drying, all dentin surfaces were bonded with Clearfil SE Bond according to the manufacturer’s instructions, and built up with resin composite. After water storage at 37°C for 24 hours, the bonded dentin specimens were prepared to an hourglass configuration with a cross-sectional area of approximately 1 mm2. Twenty specimens in each group (n=20) were subjected to a microtensile bond strength test at a crosshead speed of 1.0 mm/min. Data were statistically analyzed using One-way ANOVA and Tukey’s multiple comparisons test (P <0.05). The failure mode of fractured specimens was observed using scanning electron microscope.
Results: The specimens in the group treated with NaOCl alone had significantly lower bond strength than those in the control group. All specimens in the groups treated with PA on NaOCl-treated dentin had significantly higher microtensile bond strength than the specimens in the group treated with NaOCl alone. There were no significant differences in bond strengths between the control group and the group treated with 15% PA for 30 seconds. The failure modes were mainly mixed failure.
Conclusions: The 30-second applications of 15% PA from grape seed extract improved the strength of the bond between a two-step self-etch adhesive and NaOCl-treated dentin.
Keywords: proanthocyanidin, microtensile bond strength, sodium hypochlorite, bonding to dentin