Abstract
In our on going study of adhesion to bovine tooth substrates with 4-META/MMA-TBB resin, two painting techniques were examined to find an optimal treatment prior to bonding to EDTA pretreated tooth surface.One was the currently used single-painting technique, in which liquid monomers of the resin are applied once to pretreated tooth surface prior to bonding with the resin paste.The second was triple-painting technique, in which liquid monomers of the resin were applied to pretreated tooth surface three times prior to bonding with the resin paste.After each succeeding liquid monomers application, the prepared tooth surface becomes drier.A 1-min pretreatment with 0.3M EDTA・2Na-0.2M EDTA・Fe・Na(pH7.4)was found to be relatively effective in removing the smeared layer.Good tensile bond strengths enamel 13MPa and dentin 12MPa were obtained when the triple-painting technique was applied.A thin 1μm layer thought to be a hybrid of resin and dentin, was detected using SEM.XMA also exibited the demineralized dentin with a 1μm layer.
