UCLA

The development of pulp capping agents has been instrumental in promoting reparative dentin formation and facilitating pulpal repair in response to pulp exposure during extensive caries excavation. Although calcium hydroxide was long the gold standard for pulp capping, the development of mineral trioxide aggregate (MTA) has ushered in a new wave of therapeutic pulp capping agents and MTA derivatives, also known as hydraulic calcium-silicate cements (HCSCs). Unfortunately, little is known as to the pulpal toxicity and dentin regenerative capacity of these materials. In the current study, the physiologic effects of four HCSCs on reparative dentin and dentinal bridge formation and periapical bone loss were evaluated radiographically and histologically in mice. Pulp exposure was induced in maxillary first molars of C57/BL6 mice, and reparative potential of pulp capping materials was evaluated by CT analysis and Hematoxylin and Eosin (H&E) staining. Among the five HCSCs used for pulp capping, only Dycal failed to induce reparative dentin and dentinal bridge formation, instead inducing periapical bone loss. Although TheraCal LC also induced periapical bone loss, significantly more teeth treated with Dycal developed periapical radiolucency's. Histologically, dentinal bridge formation was observed in all HCSCs except Dycal. These findings indicate that with the exception of Dycal, all HCSC derivative materials evaluated are as effective, if not more so, than the original PROROOT� MTA in promoting reparative dentin formation and pulpal repair.