Pulp responses to the application of a self-etching adhesive in human pulps after controlling bleeding with sodium hypochlorite

Objective: To evaluate the pulp response to direct capping with self-etching adhesive systems using sodium hypochlorite as a hemostatic agent. Method and Materials: Twenty-six human third molars scheduled for extraction were selected from undergraduate students of dentistry. Class I cavities with pulp exposures were performed. To control bleeding, 2.5% sodium hypochlorite was used for 20 seconds, followed by washing with saline solution. The pulp exposures were capped with calcium hydroxide (n = 10) or adhesive system (n = 16). All cavities were restored with adhesive system and composite resin. Half of the samples of each capping material were extracted after 30 days and the remaining after 90 days. The samples were prepared for histological analysis (hematoxylin-eosin) and bacterial detection (Brown & Hopps) and evaluated according to standard ranking. Data were submitted to statistical analysis (Mann-Whitney test). Results: There was a significant difference (P .05) only in relation to dentin barrier formation. Pulps dressed with calcium hydroxide showed dentin barrier formation in all specimens, obliterating the exposure site. No inflammatory response was associated with material. In the experimental group, after 30 days, there was an attempt for healing with reparative dentin deposition, presenting a mild to moderate inflammatory infiltrate. Similar findings were found after 90 days, decreasing the inflammatory response. Bacteria were not detected in any specimen evaluated. Sodium hypochlorite was effective for hemostatic control. Conclusion: Calcium hydroxide produced better biological performance than the self-etching adhesive, and sodium hypochlorite did not interfere with the pulp repair. Parole chiave: calcium hydroxide, composite resin, dentin barrier, dentin-bonding agent, pulp capping, sodium hypochlorite