Bond strength between composite repair and polymer-infiltrated ceramic-network material: Effect of different surface treatments.

Abstract

To evaluate the bond strength of a polymer-infiltrated ceramic-network (PICN) material and to composite repair after different surface treatments. Eighteen blocks of the PICN material were obtained from CAD/CAM blocks, aged and randomly divided into 2 groups: 5% hydrofluoric acid (HF) or sandblasting with aluminum oxide particles (SAND). For each condition, three treatments were tested: silane (Sil), silane-containing adhesive (Ad), or silane + silane-containing adhesive (SilAd). The treated PICN surfaces were restored with composite resin. The microtensile bond strength test was performed in a universal testing machine, and data (MPa) were compared with two-way Analysis of variance (anova) and Tukey (α = 0.05). Roughness (Ra) and contact angle (CA) were obtained after HF and SAND conditions. The greatest bond strength values were obtained for the groups Sil and SilAd, for both HF and SAND pretreatments. The Ra values of SAND were statistically greater than HF. The CA generated by the adhesive on SAND surface was lower than HF surface. The use of silane improves the bond strength of the composite repair to PICN substrate compared to the single use of silane-containing adhesive. The HF pretreatment is most indicated when the silane-containing adhesive is applied alone. Fractured PICN restorations can be repaired with composite resin, because the surface is treated with hydrofluoric acid or sandblasting followed by the individual use of silane.