Short-term dentin-pulp complex repair with four pulp capping materials: a double-blind randomized crossover histological study

This study aimed to evaluate the histological short-term response of intact premolars following direct pulp capping (DPC) using four bioactive materials: Neo MTA Plus (NMP), Neo Putty (NP), Total Fill BC Fast set putty (FSP), and Total Fill BC RRM Paste (BCP). Thirty-two intact premolars in eight patients scheduled for orthodontic extraction were included. Teeth were randomly assigned into four groups based on the bioactive material applied during pulpotomy. Each patient will experience the four direct pulp capping materials, randomly assigned to their four premolars: NMP group (n = 8), NP group (n = 8), FSP group (n = 8), and BCP group (n = 8). Premolars were extracted after four weeks. Histological evaluations assessed pulpal inflammation intensity (PII) and dentinal bridge continuity (DBC). Kruskal-Walis and Mann-Whitney U tests were used to analyze the data. Statistical significance was set at α = 0.05. There were significant differences in the PII among groups (p = 0.001). The NMP group was lower than the other three material groups (NP, FSP, and BCP). Moreover, there were significant differences in the DBC among groups (p < 0.001). DBC in the NMP group was lower than that of the other three material groups (NP, FSP, and BCP). Additionally, the DBC in the FSP group was higher than in the NP and BCP groups. The short-term histological examination suggests that the NMP group exhibited the lowest PII but was associated with inferior continuity of the formed dentin bridge. In contrast, the FSP group demonstrated superior continuity of the formed dentin bridge.