In Vitro Effect of Different Cavity Disinfectants on Shear Bond Strength of Resin Composites to Dentin with Two Adhesive Ap-proaches

Abstract

Aim. To evaluate the effect of three different cavity disinfectants on the shear bond strength of resin composites to dentin applied with two different adhesive approaches. Methods. Eighty extracted human third molar teeth were randomly separated into 4 basic groups. GP1 is the control group (no treatment), group 2, 3 and 4 dentin surfaces were treated with the following cavity disinfectants, respectively; 0.12 % chlorhexidine solution (CHX), 5 % sodium hypochlorite (NaOCL) and 0.15 % benzalkonium chloride (BAC). Then each group was divided into two subgroups (n=10) according to the adhesive approaches. Ten specimens were bonded with the total-etch approach and the other ten specimens were bonded with the self-etching approach. The resin composite was then applied incrementally to the dentin surfaces using a cylindrical-shaped Teflon tube (3mm diameter × 3mm height). After 24h water storage in an incubator, the specimens were then mounted and tested to determine shear bond strength. Results. Dentin surfaces treated with different cavity disinfectants showed significantly higher shear bond strength than the control group. The Tantum disinfectant group had the highest shear bond strength value among the cavity disinfectant groups. For the three types of cavity disinfectant, the total-etch ap-proach showed higher shear bond strength than the self-etch approach. Conclusion. Treated the dentin surface with cavity disinfectant before adhesive bonding improved the shear bond strength between resin composite and dentin surface in particular with the total-etch adhesive approach.