The purpose of this study was to evaluate the effect of dual bonding technique by comparing micro-shear bond strength between two different luting methods of resin cement to tooth dentin. Three dentin bonding systems(All-Bond 2, One-Step, Clearfil SE Bond), two temporary cements (Propac, Freegenol) were used in this study.
In groups used conventional luting procedure, dentin surfaces were left untreated. In groups used dual bonding technique, three dentin bonding systems were applied to each dentin surface. All specimens were covered with each temporary cement. The temporary cements were removed and each group was treated using one of three different dentin bonding system. A resin cement was applied to the glass cylinder surface and the cylinder was bonded to the dentin surface. Then, micro-shear bond strength test was performed. For the evaluation of the morphology at the resin/dentin interface, SEM examination was also performed.
Conventional luting procedure showed higher micro-shear bond strengths than dual boning technique. However, there were no significant differences. Freegenol showed higher micro-shear bond strengths than Propac, but there were no significant differences. In groups used dual bonding technique, SE Bond showed significantly higher micro-shear bond strengths in One-Step and All-Bond 2 (p < 0.05), but there was no significant difference between One-Step and All-Bond 2. In SEM observation, with the use of All-Bond 2 and One-Step, very long and numerous resin tags were observed. This study suggests that there were no findings that the dual bonding technique would be better than the conventional luting procedure.