Purpose: This study examined the histological effectiveness of using Biodentine and Simvastatin as pulpotomy agents in dog molars.

Methods: A total of 64 teeth were used out of 4 healthy mongrel dogs. The 16 canine molars were separated into four equal groups in each dog, group A; without any treatment, group B; with Biodentine, group C; treated with Simvastatin and group D; treated with a combination of Biodentine with Simvastatin. At each predetermined interval, the dogs were sacrificed (4 and 9 weeks). The samples were then prepared for histological evaluation. Result: The data revealed that after 4 and 9 weeks, there was no or mild inflammatory reaction and complete dentine bridge formation for the Biodentine treated group, while Simvastatin treated group showed severe inflammatory reaction necrosis and absent bridge with a thin layer of hard tissue extending. The combination of the Biodentine and Simvastatin treated group showed mild to moderate inflammatory reaction with complete dentin bridge.

Conclusion: The histological analysis from the current study suggested that using Simvastatin alone as a pulpotomy agent failed to preserve the pulp vitality and in the formation of continued dentin bridge sealing the exposure site of the pulp of dog's teeth while adding biodentin to Simvastatin as a combination can represent a good pulpotomy agent based on the relative good histological results.