EVALUATION OF BONE HEALING BY MESENCHYMAL STEM CELLS IN RABBITS (AN EXPERIMENTAL STUDY)

Abstract

BACKGROUND: Large bone defects are considered a massive challenge in the field of oral and maxillofacial surgery. Cell Therapy using bone marrow-derived mesenchymal stem cells (BM-MSCs), as an alternative technique, has effective potentialfor bone regeneration. AIM OF THE STUDY : To compare histologically the bone healing rate of critical size defects in rabbit tibia using mesenchymal stem cells versus untreated defects. MATERIALS AND METHODS: Critical-sized defects were prepared on the tibia of rabbits. Experimental groups were divided into 2 groups: (a) Control group; untreated rabbits left for spontaneous healing, (b) collagen sponge with MSCs treated group. Sacrificing of rabbitswas done at 2 and 6-week intervals . RESULTS :Bone defects treated with BM-MSCs showed asignificant increase in the healing rate compared to the control group.Histological examination showed immature bone trabeculae lined with plump active osteoblasts with minimal amount of newly formed blood vessels andalmost no inflammatory cell infiltration at the 2-week interval. Furthermore, at the 6-weeks interval the defects were almost healed with mature thickened dense bone trabeculae lined by fattened osteoblasts with no inflammatory infiltration. CONCLUSION: BM-MSCs are a promissing tool for bone regeneration.