Regenerative Potential of Bone Marrow in Rabbit Tibia Bony Defects

Objective: The influence of bone marrow in the osteogenic outcome has not been evaluated in the healing of bony defects. The aim of this study was the evaluation of spontaneous bone regeneration in artificial tibia defects with, or without the exclusion of the bone marrow. Material and Methods: Ten (10) New Zealand rabbits were used and divided into two groups of 5 in each group. In the first group (test, PoP), the marrow cavity was emptied completely under a 6mm defect in the rabbit tibia metaphysis and replaced by CaSO4 in the form of plaster of Paris and a round piece of lyophilized collagen membrane in contact with the endosteum, resting on the plaster. In the second group (control), the bony defects were not filled with the plaster of Paris or collagen membrane. The animals were sacrificed after 8 weeks of healing and prepared for histological and histomorphometric analysis. Results: The results showed that there was statistically significant difference (p<0.05) in the newly formed bone area between the control group (mean value: 68.08 ± 12.09) and the PoP group (mean value: 54.02 ± 13.93). Similarly there was a statistically significant difference (p<0.001) between the control group (mean value: 95.99 ± 1.74) and the PoP group (mean value: 75.37 ± 13.27) for the new bone density. Conclusions: The present study confirms that the bone marrow has a significant regenerative potential in the initial healing of artificial bony defects.