Bonding of Butylborane-polymerized Resin to Dentin Primed with a Microperoxidase

Objectives: The purpose of this study was to investigate the efficacy of experimental dentin primers containing a microperoxidase (MP-11, Sigma-Aldrich). Methods: The aqueous primers contained different concentrations (0.01, 0.1, and 1.0 µmol/g) of MP-11 with and without 35wt% 2-hydroxyethyl methacrylate (HEMA). The luting agent used was a self-curing resin (4-META/MMA-TBB, Sun Medical). Bovine dentin surfaces were flattened, ground on wet 600-grit silicon-carbide paper, and etched with 10wt% phosphoric acid for 30 s. A piece of masking tape was positioned on the surface, the primer was applied to the bonding area (5 mm in diameter), and a stainless steel rod was then bonded to the specimen with the 4-META/MMA-TBB resin. After 24-hours immersion in water at 37˚C, tensile bond strengths were determined. The data were analyzed by ANOVA and a multiple comparison test (p<0.05). Results: The bond strength was significantly influenced by both MP-11 and HEMA. Groups with no MP-11 showed the lowest values regardless of HEMA. Without HEMA, the bond strengths of groups using 0.01, 0.1, and 1.0 µmol/g MP-11 were statistically identical, and also stronger than that of the no MP-11 control. In the presence of HEMA, the bond strength was significantly enhanced with an increased concentration of MP-11. The maximum bond strength was obtained with aqueous HEMA primer containing 1.0 µmol/g MP-11. Conclusion: It is concluded that the combined use of MP-11 and HEMA serves to improve the bonding between 4-META/MMA-TBB resin and dentin etched with phosphoric acid. Supported by a grant from JSPS-Japan, (B)-14771096.

Table. Mean and standard deviation of tensile bond strength (MPa)

Identical letters indicate no significant difference (p≥0.05).