Statement of the Problem: Direct pulp capping (DPC) is a proven method in which the exposed pulp is coated with a suitable material to prevent further damage and to help its repair and healing.
Purpose: The purpose of this study was to compare the response of human dental pulp after DPC with calcium enriched mixture (CEM), mineral trioxide aggregate (MTA) cement and Biodentine.
Materials and Method: In this clinical trial study, class V cavities were prepared on the buccal surfaces of 30 human premolar teeth, until the pulps were mechanically exposed. Then, teeth were randomly pulp capped with MTA, CEM cement and Biodentine, followed by Resin modified glass ionomer filling. The fourth group was control (n = 10), which were extracted without any intervention. Six weeks after the intervention, the teeth were extracted and prepared for histological evaluation in terms of the type and degree of pulp inflammation, dentin bridge formation and the presence of necrosis. Data were analyzed using Kruskal-Wallis and Mann Whitney U tests.
Results: In all groups, Necrosis was not observed and inflammation was chronic. The Biodentine group exhibited significantly more pulpal inflammation compared with the other groups (p= 0.001). There were no significant differences among CEM cement, MTA and Biodentine in terms of dentine bridge formation. The thickness of dentin bridge formed in the Bidonetine group was significantly higher than MTA and control groups (p= 0.035 and p= 0.011, respectively).
Conclusion: Although dentin bridge formation and the thickness of dentin bridge formed in the Biodentine group were higher than the other groups, pulp showed greater inflammation compared to CEM cement and MTA. The results of this study suggested that MTA and CEM cement performed better as the direct pulp capping material.