Histopathological Assessment of Tricalcium Aluminate-free Mineral Trioxide Aggregate and Two Antibacterial Enhanced Mineral Trioxide Aggregates As Pulpotomy Agents in Rat Model

Objective: To evaluate the effect of a newly developed MTA-based material and two antibacterial-enhanced MTAs as pulp capping materials in immature permanent dental elements underwent full pulpotomy. Methods: The present animal study included 20 Wistar albino rats that, after full pulpotomy, were randomly divided into 4 groups receiving different MTA formulations as pulp capping materials: conventional MTA, Tricalcium aluminate (TCA)- free MTA, and MTA enhanced with metronidazole or doxycycline. Histopathological assessments were carried out at 7- and 28-days post-treatment to evaluate dentinal bridge formation, inflammatory reactions, pulp tissue necrosis and internal resorption. Results: Seven days post-treatment, all groups exhibited inflammation and pulp necrosis, that were minimal in Groups III and IV than Group I. Group II showed a statistically significant difference only in terms of pulp necrosis (p<0.001). At 28-days all Groups showed slight inflammation and pulp necrosis, mainly in Groups I. Dentinal bridge formation was appreciated in all samples belonging to Groups II, III and IV and in 7/10 specimens of Group I, resulting in a statistically significant difference (p <= 0.001). Conclusion:TCA-free MTA and antibiotic-enhanced MTAs showed superior performances in dentinal bridge formation and exhibited minimal pulpal necrosis than conventional MTA. The inclusion of antibiotics might contribute to create a more sterile environment that would improve the outcomes, favoring deposition of a mineralized matrix. However, further studies are needed to support these preliminary results.