Direct pulp reactions to different self-etch adhesive systems in short-term

Objectives: This study is to evaluate the mechanically exposed dog pulp response to three different self-etch adhesive systems.Methods: Class V cavities were Seventy-two Class V cavities were prepared under the isolation of rubber dam in dogs. The pulps were exposed with ISO1/2SS round burs or a probe. The control group was capped with Dycal, while the experimental groups were capped with Clearfil SE Bond (Kuraray, Japan), Imperva-Bond (Shofu, Japan) and Prompt L-Pop (3M ESPE, USA) respectively. Routine histopathological process was performed at 7, 14 and 30 days postoperatively. H&E staining was carried out to assess the inflammatory cell response, tissue disorganization and hard tissue formation. Brown&Brenn staining was used to detect the presence of bacteria. The results were analyzed by Kruskal- Wallis and Nemenyi test. Furthermore, the inner surface of the resin restoration was observed by SEM.Results: Moderate to severe inflammatory response is the main pulpal reaction. Hard tissue formation appeared at 14~30 days. Positive bacterial staining was about 75% overall. A cluster of cocci was observed in the pulp surface of restoration by SEM. The histological features of experimental groups were inferior to control group. There existed difference between the three self-etch systems.Conclusion: Different self-etch adhesive systems had diverse stimulate to the pulp. The histopathological changes of adhesive systems were worse than that of Dycal. So it is not suggested to cap the pulp directly with self-etch adhesive systems.