Influence of additional acid etch treatment on resin cement dentin infiltration.
PURPOSE: The purpose of this study was to compare the penetration of a resin cement into dentin surfaces pretreated with self-etching primer with or without conventional acid etch. MATERIALS AND METHODS: Dentin surfaces of 8 unerupted human third molars were treated with self-etch primer (Panavia 21; Kuraray Co, Ltd, Osaka, Japan) with or without conventional acid etch treatment. A resin cement (Panavia 21) was applied according to manufacturer's instructions. Dentin/resin cement interface sections from each tooth were examined with light microscopy and scanning electron microscopy. In the light microscopy sections, exposed protein at the dentin/cement interface was stained a distinct red with Goldner's trichrome. RESULTS: The resin cement did not penetrate the depth of the zone of demineralized dentin when the self-etch primer was used in combination with conventional acid etch treatment. Inadequate resin cement penetration leaves a substantial area of exposed protein at the dentin/cement interface. In contrast, there was complete resin cement diffusion throughout the demineralized dentin when the self-etch primer was used without acid etching. CONCLUSIONS: Combining conventional acid etch treatment with a self-etching primer/resin cement system resulted in incomplete resin cement penetration and exposed protein at the dentin/cement interface.