Effect of grape seed extract on the bond strength and adhesion durability of universal adhesive to dentin

Abstract

The effects of grape seed extract (GSE) on the microtensile bond strength (µTBS) and resin-dentin bond durability of universal adhesive to dentin were investigated, while the resin-dentin interface was evaluated using a scanning electron microscope (SEM). Flat occlusal dentin surfaces of 80 sound human molars assigned to, control and GSE-pretreated groups & further divided into etch-and-rinse (E&R) and self-etch (SE) adhesion subgroups. In each subgroup, molars tested immediately (t0; n = 10) & after 6 months (t6; n = 10). In GSE-pretreated group, 10% GSE was prepared in hot water & then used for 1 min pretreatment after etching (15s) in the E&R subgroup or before application of adhesion in the SE subgroup. Composite build-ups made incrementally, and dentin beams sectioned and tested for µTBS at the baseline (24 h) and 6 months. Sections were obtained for SEM analysis. In the 6-month treatment, beams stored in artificial saliva, subjected to thermal cycling, and then tested. The failure modes of fracture surfaces were identified with a stereomicroscope. Comparing the t0 and t6 timepoints, significant reduction in µTBS in all groups compared with their respective controls after aging, but the percentage of bond loss due to aging in the GSE-pretreated groups was less than controls. Most failure modes were mixed. GSE (10%) pretreatment for 1 min before adhesion enhanced the durability of the resin-dentin bond but did not completely eliminate loss of bond strength.