The aim of this study is to evaluate the effect of mesenchymal stem cell (MSC) on the regeneration of distraction osteogenesis on irradiated mandible of adult rabbit. Ten adult rabbits were randomly selected and the dorsal fat penicle was removed for harvesting and culture of mesenchymal stem cells. The mandibles were irradiated on a single dose of 40 Gy. After 30 days the animals were underwent to mandibular lengthening by distractions osteogenesis, being divided on two groups. At the end of active distraction, the distraction callus were injected with saline solution on the control group and MSC on the study group. After consolidation phase (4 weeks) the mandibles were removed and the evaluated by histomorphometric analysis on 7 μm section stained with haematoxylin and eosin. Data were analyzed using Graph Pad Software and ANOVA test (0.05). The histomorphometric analysis demonstrated increase of new bone formation on the study group (MSC) compared to the control group. The injection of adipose derived mesenchymal stem cell is able to improve bone regeneration on irradiated distraction callus on mandible.

Key words: distraction osteogenesis; stem cells; tissue engineering

Ethical protocol: UNIFESP 0333/12.