Ethanol-wet bonding may enhance infiltration of nanofillers into dentinal hybrid layers

Abstract

The objective of the present study was to examine nanofillers from two adhesives, Single Bond 2 and Prime & Bond NT along dentinal hybrid layers using energy dispersive x-ray spectroscopy (EDS) under ethanol-wet bonding or water-wet bonding conditions. Prepared dentin samples from twelve bovine incisors were divided into four groups randomly according to bonding technique and dentin adhesive system as following; (I) Single Bond 2 + water wet bonding technique, (II) Single Bond 2 + ethanol wet bonding technique, (III) Prime & Bond NT + water wet bonding technique, (IV) Prime & Bond NT + ethanol wet bonding technique. Bonded teeth were sectioned into 1-mm thick resin-dentin slabs. One slab from center of each tooth was used, totaling three slabs for each test group. Silicon detection within dentinal hybrid layer was measured with EDS in three regions across the photographed interfaces. Ethanol-wet bonding technique increased silica uptake within dentin hybrid layers interfaces of Single Bond 2 and Prime & Bond NT. However, there was no significant difference between Prime & Bond NT groups. Ethanol-wet bonding may enhance nanofiller infiltration into demineralized dentin matrices, thus may improve mechanical properties of hybrid layers. However, benefit may depends on solvent/monomer composition of resin adhesive system.