Dissolution of bovine pulp tissue by endodontic solutions

Pulpal tissue was incubated at 37°C for 10 min with various solutions used for root canal therapy. The dissolved material was assayed for hydroxyproline (HYP) and total phosphate, and the insoluble residue for HYP and dry weight. Sodium hypochlorite (NaOCl) at 5% and diluted to 2.5% showed the strongest solvent capacity measured as loss of HYP and weight from the tissue. Dilution to 0.5% significantly decreased the effectiveness of NaOCl. The absence of HYP from the NaOCl extracts suggested decomposition of this amino acid. The other solutions tested were far inferior in their ability to dissolve pulpal tissue. The demineralizing solutions tested were poor solubilizers of soft tissue; however, they caused a considerable increase in the amount of phosphate released.