Abstract
We have been studying adhesive resins to dentin by using new methacrylates with hydrophobic and hydrophilic groups such as 4-methacryloxyethyl trimellitate anhydride(4-META).During studies on adhesion mechanism of a 4-META/MMA-TBB resin to dentin, it was found that the denaturation of dentinal collagen during acid etching decreased the bond strength to 6MPa, and that the preservation of the higher structure of the protain by application of glutaraldehyde or FeCl3 in the pretreatment for the bonding was essential to obtain higher bond strength(11〜18MPa)to dentin.A new bonding agent without TBB was developed in this study.It consists of two components, one is 2wt% 4-META in a monomer mixture of 20% HEMA and 80% MMA containing 0.5wt% BPO, and the other is 2wt% p-toluenesulfinic acid sodium salt and 5% glutaraldehyde in ethanol.The tensile bond strength treated with 10-3 for 30 sec, 0.5M EDTA 2Na for 60 sec or 65% phosphoric acid for 30 sec were 13, 9 or 19MPa respectively.The treated dentin was first applied to the bonding system, and then joined to a PMMA rod with conventional BPO-amine self-curing resin.
