Bond Strength of a Self-Etch Adhesive Used with Various Composites

Objectives: The aim of this study was to evaluate microtensile bond strength of a self-etching and dual-curing dentin adhesive (Futurabond NR) in comination with different light- and self-curing resins (Rebilda, Grandio, Tetric Ceram, Clearfil Core, Multicore) on perfused dentin in vitro. Methods: 105 freshly extracted molars, stored in saline for a maximum of fourteen days after extraction were included. All teeth were specially prepared allowing the simulation of dentin perfusion. Dentin specimens with a total thickness of 3.5 mm were obtained under standardized conditions. The specimens were randomly assigned to seven experimental groups of fifteen samples each: Group 1: Futurabond/ Rebilda (light-curing), Group 2: Futurabond/ Grandio (light-curing); Group 3: Futurabond/ Tetric Ceram (light-curing), Group 4: Futurabond/ Rebilda (self-curing), Group 5: Futurabond/ Clearfil Core (self-curing), Group 6: Futurabond/ MultiCore (self-curing), Group 7: AdHeSE/ Multicore (self-curing).  Microtensile bond strength was measured 15 minutes after application an universal testing machine. Results: For the seven test series following microtensile bond strengths were evaluated (mean value and standard deviation in MPa):

Futurabond NR in combination with Grandio (group 2) and Clearfil Core (group 5) showed the highest bond strengths  (p< 0.05, Bonferroni-Holm). Focusing on the self-polymerizing resins, significant lower bond strengths were observed in group 4 (Rebilda) and 6 (Multicore) compared to group 5 (Clearfil Core) (p< 0.05, Bonferroni-Holm). Conclusions: It can be concluded that all bonding agents used in this study were able to establish bond strength on perfused dentin. Futurabond NR used with light-polymerizing resins showed well bond strengths in all groups (1, 4, 5). In combination with self-polymerizing resins different bond strengths were evaluated.