Abstract
Aim: to evaluate the bioactivity of Biodentine compared with ProRoot-MTA. Methods: Standardized cavities were prepared in 20 dentin blocks and filled with either Biodentine or ProRoot-MTA(10 each). Each group was then subdivided into two subgroups; one was kept in deionized water, and the other in phosphate buffer solution (PBS) for 28 days. Bioactivity was determined at the material surface and material-dentin interface using Scanning Electron Microscope with Energy Dispersive X-ray. Results: Samples of Biodentine and ProRoot-MTA stored in deionized water showed microporous granular structure interrupted by few large hexagonal-shaped grains. Their surface elemental analysis showed similar main constituents including carbon, oxygen, and silicon with no statistically significant difference between both materials. Biodentine contained significantly more calcium than ProRoot-MTA. Unlike ProRoot-MTA, calcium and strontium were significantly decreased at the interface of Biodentine than that at the material's surface. After 28 days incubation in PBS, an apatite layer was formed at both the material surfaces, and the material-dentin interface exhibited as globular structure with entangled rod-like appearance for Biodentine or circular-shaped with flower-like deposits for ProRoot-MTA. There was no significant difference in calcium/phosphate ratio between Biodentine (3.52 +/- 1.34 wt. %) and ProRoot-MTA (3.89 +/- 1.27 wt. %) filled samples. Conclusion: The immersion of Biodentine and ProRoot-MTA in PBS resulted in the formation of comparable apatite layer that wasn't formed when these materials were immersed in deionized water indicating their bioactive property.