Does roughness of dentin-surface influence newly-developed all-in-one bond-strength to dentin?

Objectives: There are many reports which indicate the influences of dentin surface conditions on the bond strength of all-in-one adhesive system. The purpose of this study was to evaluate the influence of rough dentin surface on newly commercialized all-in-one adhesive systems.

Materials and Methods: Two all-in-one adhesive systems, BOND FORCE (BF, TOKUYAMA), Optibond All-In-One (OB, Kerr), one 2-step self-etch-system, Clearfil SE Bond (SE, Kuraray) and composite resin, ESTELITE P-Quick (TOKUYAMA) were used. Eighteen intact extracted human third molars according to the ethic committee of Hokkaido University's regulation were cut to expose the dentin surface. Half of them were ground with #600 and the others were ground with #180 silicon carbide paper. Additionally, they were randomly divided into 3 groups per each. After adhesive procedures were done, all the specimens were kept in 37 Celsius degree water for 1 day and they were cut to perform the micro-tensile bond strength test. The data was analyzed using the One-way ANOVA and Bonferroni test (p<0.05).

Results: The table showed the bond strength (S.D.).

SE#180 showed significantly higher bond strength than BF#180 and OB#180. BF#600 showed significantly lower bond strength than SE#600. The bond strength of OB#180 was significantly lower than OB #600.

Conclusions: The difference of dentin surface was influenced only on OB. The bond strengths of BF were quite low with both surfaces, while two-step adhesive obtained high bond strengths in both condition. The bond strength of BF and SE were independent of smear condition although SE showed higher bond strength than BF in both surface.