Bone Defect Regeneration Using Mesenchymal Stem Cells from Bichat's Fat Pad

The aim of the study was to assess the efficiency of the mandibular bone defect regeneration by administering mesenchymal stem cells (MSC) from the Bichat's fat pad (B-MSC), as well as the osteoblasts differentiated from them, according to the morphological findings.

The experimental study was carried out on male Wistar rats (n=120) aged 2 months, weighing 250-300 g. B-MSCs and the osteoblasts differentiated from them were used for the regeneration of rat mandibular bone defects formed by a round bur. In the control group, the defect was not filled, the defect was healing under the blood clot. The biopsy specimens were histologically examined on days 14, 30, and 90 after the injury formed.

The infiltration of the bone defect site by inflammatory cells was revealed for all study groups 14 days after the injury. The groups with cell administration showed the resorption of bone trabeculae (B-MSC and osteoblast groups) and a large number of capillaries (an osteoblast group). On day 30 after the injury, the preparations of the groups with cell administration demonstrated a large number of capillaries (B-MSC and osteoblast groups) and primitive bone trabeculae with osteoblasts (an osteoblast group). Active osteoclastic resorption and inflammatory infiltration were revealed in the control group. The groups with cell administration 90 days after the injury, in contrast to the control group, were found to have the formation of spongy mature bone tissue (B-MSC and osteoblast groups), the presence of bone mineralization and myeloid bone marrow (an osteoblast group) in the bone defect zone. It indicated high regenerative potential of the cells used when replacing a bone defect and the significant reduction of a regeneration period.