Abstract
We have been studying adhesives to tooth substrates and the adhesion mechanism.It was found that phosphoric acid etching demineralized the dentin and the denaturation of collagen was also taken place during the etching.A weakened surface layer on dentin where adhesives were applied was formed due to the reaction.Dentinal plugs were also dissolved away by the acid.Affection of zinc phosphate cement on dentin during the setting of prosthetics was expected to be the same as the acid etching prior adhesion.Dentin surfaces modified by a zinc phosphate cement were observed by SEM after removal of the cement at several intervals.The observation was also carried out on the dentin treated with the liquid in the cement.The tensile adhesive strength to the dentin treated with the cement which was washed out was lower than that to the dentin etched with the acid.The glue was 4-META/MMA-TBB resin.The anticipation was confirmed through the experiments written above.Chemical modification of dentinal collage with glutaraldehyde could minimize the adverse effect of the cement on dentin during the cementation.
