Influence of preheating the bonding agent of a conventional three-step adhesive system and the light activated resin cement on dentin bond strength

AIMS: to evaluate the influence of preheating the bonding agent (Scotchbond Multipurpose Adhesive/3M ESPE) and the light-activated resin cement (RelyX Venner/3M ESPE) on dentin microtensile bond strength. MATERIALS AND METHODS: The exposed flat dentin surface of 40 human third molars were randomly distributed into four groups for cementation (SR Adoro/Ivoclar Vivadent) (n = 10): G1-bond and resin cement, both at room temperature (22°C), G2-bond preheated to 58°C and cement at room temperature (22°C), G3-bond at room temperature (22°C) and the cement preheated to 58°C, G4-bond preheated to 58°C and cement preheated to 58°C. Sticks of dentin/block set measuring approximately 1 mm(2) were obtained and used for the microtensile bond strength test. All sticks had their failure mode classified. STATISTICAL ANALYSIS USED: Factorial analysis of variance was applied, 2 × 2 (bond × cement) (P < 0.05). RESULTS: Preheating the bonding agent (P = 0.8411) or the cement (P = 0.7155), yielded no significant difference. The interaction bond × cement was not significant (P = 0.9389). CONCLUSIONS: Preheating the bond and/or the light-activated resin cement did not influence dentin bond strength or fracture failure mode.