MTA as an Osteoinductive Biomaterial: In Vivo Results

Objective: to assess by means of Backscattered Electron Microscopy (BEM) the osteoinductive effects of MTA in bone deffects observed by MicroCT. Methods: Two surgical deffects were produced in the tibia of eight adult male New Zealand Rabbits. One deffect was filled with MTA, while the second was maintained as control, to assess the spontaneous recovery of the osseous tissues. The animals were sacrificed after eigth weeks, and the tibiae extracted to be studied by BEM after being submitted to microCT exploration.

Results: The micro CT observation showed that eigth weeks after the intervention the surgical deffects filled with MTA were completely closed, while the control deffects were not totally recovered. When observed by BEM, the biocompatibility evidenced by the MTA was proven by its direct contact with the cortical lamellar bone, without presence of Howship’s lacunnae. Osteoconduction was evidenced by the presence of bone growth in direct contact with the biomaterial, both in the external oseous surface and in the lesional cortical surface. Moreover, haversian remodeling of the cortical bone structure was found substituting both the preexisting cortical bone and the MTA.

Conclusion: MTA seems to be confirmed as a potential osteoinductive biomaterial.