A research on bond strength and interface of dentin adhesives / 实用口腔医学杂志

ABSTRACT

Objective: To evaluate bond strength and interface of various dentin adhesives by a modified interface processing method. Methods:Nine extracted human molars were ground to expose fresh dentin surface. Three dentin adhesives (Single Bond, Clearfil SE Bond and Clearfil S3 Bond) were applied respectively and a block of composite resin was built up. The specimens were then stored in distilled water for 24 h at 37 ℃ and sectioned into beams of 0.9 mm×0.9 mm cross-sectional area. The microtensile bond strength was determined with Microtensile Tester(n=15). In addition, the bonding specimens were conditioned with 6 mol/L HCl, 5% NaOCl and 0.08 mg/ml hyaluronidase to observe the adhesive interfaces by SEM. Results: Significant differences in bond strength were observed among the three adhesives(P<0.05) SE Bond (45.06±5.29) MPa> Single Bond (35.50±6.40) MPa> S3 Bond (30.46±3.82) MPa. Single Bond showed resin tags about 9-12 μm long and gaps between hybrid and adhesive layers. No obvious boundary between hybrid layer and adhesive were observed for both SE Bond and S3 Bond, while the length of resin tags were 9-14 μm and 4-7 μm for SE Bond and S3 Bond respectively. Conclusion:The morphology of the bond interface of dentin adhesive has a relationship with the bond strength.