Interfacial sealing between normal dentin and caries-affected dentin with glass-ceramic and three types of bonding systems.

To compare the bonding effect of normal dentin (ND) and caries-affected dentin (CAD) on the surface of glass-ceramics using three types of bonding systems.39 teeth with caries involving the superficial layer of dentin were randomly divided into three groups and two subgroups: nanoleakage group (n=5) and shear bond strength group (n=8). The infected dentin was removed, and the CAD was retained. The surface of the tooth was polished, and one 2 mm × 2 mm × 4 mm CAD block and one 2 mm × 2 mm × 4 mm ND block were made. The total-etch adhesive A, self-etch adhesive B, or self-adhesive resin adhesive C were used to bond the glass ceramics. The bonding specimens of the nanoleakage group were stained with ammoniated silver nitrate and observed. In the shear bond strength group, the maximum load of the loading head F (N) was recorded, and the shear bond strength of the specimen was calculated.The nanoleakage values were significantly lower than those in the CAD group. The nanoleakage value of group B was significantly higher than that of group C, and that of group C was significantly higher than that of group A. Both dentin type and adhesive type had an effect on shear bond strength; under the same adhesive system, normal dentin demonstrated higher shear bond strength than CAD. However, the shear bond strength of adhesive A was higher than the bond strengths of adhesives B and C, but there was no significant difference in shear bond strength between adhesives B and C.This study showed that dentin type and bonding system influenced shear bond strength and nanoleakage. The total-etch adhesive system showed the best interfacial sealing and bonding effect.