Aim : This study aim to evaluate the physicochemical properties (pH, calcium ion release, solubility and setting time) of different pulp capping materials [Bioaggregate (BA), Nano Bioactive glass (NBAG), Nano MTA& MTA] in vitro, and to observe the histopathological pulp response following direct pulp capping of dog's teeth.
Material &Methods : for the weight loss, pH changes and calcium ions release, the tested specimens were immersed in distilled water. The solubility tests recorded weight loss of the test materials after immersion in distilled water. The evaluations were performed at 1h, 24h and 7 days. For the histological evaluation twenty adult dogs were used in this study, (8 teeth for each dog), classified into 4 experimental groups as follows :Group 1: BA. Group 2: NBAG. Group 3: MTA. Group 4: NMTA, the pulpal tissue response was assessed at 1 month and 3 months time intervals.
Results: Bioaggregate showed the highest mean values for ph, ca ions release and solubility tests, while MTA showed the highest setting time mean value. On the other hand, Nanobioactive glass was the only material which recorded negative solubility. Histological results showed that dental pulpal tissues of teeth capped with MTA revealed absence of inflammatoion in addition to tubular pattern dentin bridge formation at site of exposure, BA showed dentin bridge formation and minimal inflammatory reaction, NMTA and NBAG enhanced the dentin bridge thickness, but of inferior quality than MTA and BA.
Conclusion: based on histological analysis MTA and Bioaggregate are favorable materials for direct pulp capping, however BA revealed the superior physicochemical properties.