Hybrid Membrane on Tooth Substrate

Abstract

2-(Methacryloyloxy)ethyl 4-methoxyphenyl hydrogenphosphate (CH₃O-OH monomer), which is a new phosphate monomer with hydrophobic and hydrophilic groups, is effective to give adhesion to tooth substrate partly for its biocompatible nature. The bond strength between dentin treated with 10% citric acid and 3% iron (III) chloride (10-3 solution) and CH₃O-OH monomer/MMA-TBB resin was 17 MPa. Using a bonding agent containing CH₃O-OH monomer and BPO-sulfinic acid initiator, the bond strength between dentin treated with 10-3 solution and selfcured resin was 10 MPa, and that was 13 MPa in case of dentin treated with 0.3 mol⋅dm^-3 EIDTA. The monomer inter-penetrated into dentin and polymerized was confirmed by SEM and TEM observation of the bonded tissue. A HCl insoluble dentin layer modified, by the interpenetration in the subsurface of tissue was observed. The layer on dentin surface is a resin reinforced dentin and has better resistance against decalcification than the original. The layer is a hybrid of natural tissues with biocompatible artificial materials.