Abstract
Polymerization of the MMA/TBBO resin was investigated in the presence of a collagen sheet treated with various treatment solutions in order to clarify the mechanism of effectiveness of ferric ion in the abhesion between MMA-PMMA/TBBO resin and dentin. The treatment solutions employed were aqueous solutions of ferric chloride (FC) or various ferric salts and citric acid (CA). Although FC-CA solution hindered polymerization of MMA at high FC concentrations, curing time of the resin decreased by the dilution of the treatment solution. Polymerization was promoted most effectively by the treatment solution of 0.50 wt% FC-1.67 wt% CA.The polymers formed were separated mechanically and by stepwise extraction. The molecular weight of the polymers depended on their location. The value was higher for polymers located closer to the inside of a collagen sheet. When the treatment solution promotes polymerization of MMA, FC-CA solution, in the presence of collagen, may improve adhesion of MMA resin to dentin through first fast curing of the resin inside collagen, the enhanced molecular weight of polymer inside collagen and graft polymerization onto collagen.
