Incorporation of selenium nanoparticles into mineral trioxide aggregate used as a direct pulp capping material

This study evaluated the histopathological response of the dental pulp following direct pulp capping (DPC) using Mineral Trioxide Aggregate Repair High Plasticity (MTA Repair HP) supplemented with green-synthesized selenium nanoparticles (SeNPs). The objective was to determine how SeNP concentration influences the biological behavior of MTA HP and to identify the dose that best supports pulp healing compared with MTA HP alone.

Twelve male dogs with 132 teeth were included. Twelve teeth served as negative controls, while 120 teeth were assigned to five groups: MTA HP alone or MTA HP combined with 0.5%, 1%, 1.5%, or 2% (w/w) SeNPs (n = 24 per group). Standardized pulp exposures were created and treated according to group allocation. Samples were collected at 7, 14, 30, and 60 days (n = 6 per interval) for histopathological assessment of inflammation, necrosis, and reparative dentine formation.

The group treated with 1% SeNP had the best results. They displayed very little inflammation, no signs of tissue necrosis, and started forming reparative dentine as early as day 14. While inflammation diminished over time in all the groups, the statistical analysis showed that the different SeNP levels made a difference in how much inflammation occurred, how much tissue necrosis there was, and the quality of the new dentine.

Adding SeNP to MTA HP depended on the amount used. The 1% version presented the best biocompatibility and assisted pulp tissue heal better. On the other hand, higher amounts triggered more inflammation. Overall, these results recommend that 1% SeNP-enhanced MTA HP could be a choice for direct pulp capping, offering better healing and clinical results.