SEM and TEM Observation of Ultra Microstructure at Adhesive Interface between Resin and Caries Affected Dentin

To prevent over-cutting of the sclerotic dentin, we developed a new caries detector (Caries Check, Nippon Shika Yakuhin Co., Ltd., Japan) composed of polypropylene glycol containing acid red. The purpose of this study was to observe the ultra microstructure of the adhesive interface between resin composite and dentin after cutting the dentin in accordance with the conventional Caries Detector or Caries Check staining. In the Caries Check specimen, the dentin tubules were filled with debris and penetration of the bonding agent was limited in the peri-tubular dentin. In the Caries Detector specimen, the dentin tubules were open and a resin tag formed in the dentin tubules. It was possible to conclude that the sclerotic dentin was preserved under the guide of staining by Caries Check. The results suggest that dentin bonding was not obtained by monomer penetration into the superficial substrate dentin or into the dentin tubules.