Effect of Cross-Linking Agents on Sound and Caries-Affected Dentin Bonding

Objectives: To evaluate the effect of Grape seed extract (GSE) and Glutaraldehyde (GA) on the bond strength of sound and caries-affected dentin. Methods: Human molars presenting occlusal caries were used. Caries detector solution (Kuraray Dental Co.) was applied to the flat dentin surface in order to identify sound and caries-affected dentin, in which 600-grit abrasive paper was used until caries-affected dentin was exposed. The flat dentin was etched for 15s using 37% H₃PO₄ (3M/ESPE). Teeth were randomly divided into groups according to the type of treatment received before bonding. Control: No pre-treatment. Bonding protocol was followed according to manufacturers' instructions for each adhesive system (Single Bond Plus–3M/ESPE or One Step Plus-Bisco) and light-cured for 20s. After completion of the bonding procedure, a composite build-up was made; GA: prior to the application of bonding agent, the etched dentin surface was treated with a 5% glutaraldehyde for 1 hour, rinsed with distilled water and followed by the bonding/build-up protocol as described for Control group; GSE: the etched dentin surface was treated with a 6.5% GSE for 1 hour, rinsed and then subjected to bonding/build-up in the same manner as for Control group. The bonded specimens were stored in water for 24h, and were sectioned into beams with a cross-sectional area of 0.7 mm².  Microtensile testing was done using an EZ-Test apparatus, and the data were analyzed using ANOVA for each adhesive and Fisher's PLSD test at a=0.05.  Results: MTBS (MPa ±SD) are summarized in this table: