Figure 1. Bond strength results and fractographic analysis. (A) Tensile bond strength (mean ± standard deviation) (upper) and area fractions of failure modes on fractured surfaces for each resin system (lower). Groups with tensile bond strengths that were significantly (p < 0.05) different are indicated by different lower-case letters: two-way ANOVA and Fisher's PLSD test. n = 20 for each group. (B) Simple regression analysis comparing the bond strength and the percentage of each failure mode. OS, One-Step; PB, Prime & Bond NT; C, resin composite; B, bonding resin; TH, top of hybrid layer; WH, within hybrid layer; DD, demineralized dentin; BS, bond strength.
