Surface Conditioning Improving the Adhesion between Posts and Resin Cements

Objectives: This study evaluated the influence of surface treatments on the microtensile bond strength between a glass fiber post and different resin cements. Methods: Forth-five posts were assigned to three groups: Control group (G1); 96% alcohol-10 min (G2); 24% H2O2-10 min (G3). Each group was divided into 3 subgroups: UniCem/3MESPE (UN); BisCem/Bisco (BC); and Panavia F/Kuraray (PN). Posts (Reforpost/Angelus) were placed in a square-shaped matrix, in which it was held in place by the resin cement and subsequently photo-cured. Blocks were stored in water at 37 oC for one week, serially cut into sticks and then loaded onto a micro-tensile testing machine. Results: Mean and SDs of µTBS in MPs investigated resin cements and different surface treatment were: UN/G1: 6.80 (1.72), UN/G2: 11.08 (2.71), UN/G3: 14.00 (1.77), BC/G1: 10.96 (1.35), BC/G2: 12.03 (3.46), BC/G3: 14.31 (2.89), PN/G1: 10.38 (1.86), PN/G2: 15.35 (3.10), PN/G3: 13.37 (2.15). ANOVA indicated significant differences among surface treatments (p<0.001) and resin cements (p<0.05). The Tukey test revealed that the G3 had greater bond strength than G2 without a statistical difference (p>0.05). G1 had lower bond strength values (p<0.05). The values for BC and PN were significantly higher than UN (p<0.05). Conclusions: The post surface pre-treatment with alcohol and hydrogen peroxide significantly increased the bond strength between silanized glass fiber posts and resin cements. The bond strength was also significantly affected by the type of resin cement used and one self-adhesive resin cement (BisCem) exhibited similar bond strength values compared with conventional resin cement (Panavia F).