Cryopreservation Effect Of Human Mandible And Establishment Of Experimental Bone Bank

PUOROSE:To establish an experimental bony tissue bank and evaluate the cryopreservation effect of human mandible,with an attempt to explore the possibilities of applying cryopreserved bone(with cryoprotectant)for reconstruction of bone defects.METHODS: The bony tissue specimens harvested from the donors aged from 15 years old to 80 years old who had impacted wisdom teeth necessitating extraction in the Department of Oral Surgery,Shanghai Ninth People's Hospital,Shanghai Jiao Tong University School of Medicine.Piezoelectric osteotomy were applied to acquire and pretreat the specimens,which were then packed individually with cryoprotectant and programmed cryopreserved in-80? refrigerator by slow-rate freezing.After registration of the information necessary,the experimental bony tissue bank was set up.The cells migrated from the fragments which were subjected a prescribed freezing period of 0,1,6,or 12 months were observed by inverted microscopy.The cell viability was evaluated by WST-8,and real-time PCR was used to detect the mRNA expression of Runx2,ALP and OCN.Alkaline phophatase and alizarin red staining were utilized to detect the osteogenic capacity in vitro.Cell senescence was evaluated by a histochemical staining with a Senescence Detection Kit and karyotyping was performed,as well as the cellular apoptosis.All statistical analysis was performed using SPSS 17.0 software package.RESULTS: Cells could migrate from the different fragments,proliferate well with no significant difference in the cell senescence,cellular apoptosis and osteogenic capacity in vitro(P>0.05).CONCLUSION: Cells derived from cryopreserved bone fragments could maintain good proliferation activity and osteogenic phenotype.It is feasible to utilize the cryopreserved bone to reconstruct bone defects.