Preliminary Study On Tissue Engineering Bone Constructed By Platelet-Rich Fibrin/Heterologous Bone Composite Scaffolds

Objective:To prepare a platelet-rich fibrin/heterologous bone scaffold which can not only maintain the volumes of graft but also effectively form the new bone, and the experiment should indicate the feasibility and effectiveness of this composite scaffold for bone tissue engineering.Methods:1. Preparation of composite grafts:(1) The platelet-rich fibrinogen and thrombin were prepared;(2) The bone marrow mesenchymal stem cells were cultured and identified;(3) The composite grafts were prepared;(4) The Micro-CT was used for the observation of composite grafts;2. In vivo experiment results:(1) The composite grafts were subcutaneously implanted in nude mice;(2) After6months, the specimens were resected for the determination of volume maintenance rate of composite grafts and the histological evaluation;(3) The persistent micro-CT was used for the observation of volume changes of composite grafts and change degree of hard tissues;Results:1. The platelet-rich fibrin/Bio-Oss composite scaffolds and composite grafts were successfully prepared.2. The results of Micro-CT measurements showed the composite graft volume was401±31μ mL, hard tissue rate was42.5±4.4%. The comparison between actual data and the measurement results showed their difference was not statistically significant (P>0.05).3. After subcutaneous implantation, these nude mice didn’t have any inflammatory response, the volume maintenance rate of the specimens was90%, the new bone formation rate was16.8±6.4%. The resorption rate of heterologous bone was6.93±0.69%, hard tissue rate was65.5±6.9%.4. The results of Micro-CT observations showed that the composite graft volume before implantation was400±33.9μmL, the composite graft volume after12weeks was365±23.8μmL; the hard tissue rate before implantation was42.1±2.0%, the hard tissue rate after12weeks was39.1±1.9%. Their differences were not statistically significant (P>0.05).5. The results of persistent micro-CT observations on the bone formation in vivo showed that the bone formation of PRF/Bio-Oss/BMSCs/BMP-2bone grafts reached a peak within4-6weeks.Conclusion:Platelet-rich fibrin/Bio-Oss composite scaffold is a biodegradable scaffold conducive to new bone formation and maintenance of composite graft volume for bone tissue engineering.