Biomimetic Design And Preparation Of Bone Tissue Engineering Scaffolds

It is now generally recognized that repairing of defect bones is one of the major issues in bone tissue engineering research. Nowadays in clinic massive bone defect of injured, infected and tumor removed has not been effectively solved, however. The present research will focus on the most suitable scaffolds acted as substitute of bone tissue. The design and fabrication of bone tissue engineering scaffolds are crucial for the study of thermodynamics and Dynamic mechanical performance ofβ-tricalcium phosphate /poly-lactic acid composite scaffolds. The results will speed up the development of bone tissue engineering scaffolds and their application in clinic.The bone model was designed by volume rendering technique. Composite scaffolds were prepared using poly-lactic acid andβ-tricalcium phosphate as raw materials via sodium chloride as porogen by membrane lamination-salt leaching technique, and composite fibres were prepared adopting melting spinning technique. Gel Permeation Chromatographic (GPC),Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Differential Scanning Calorimeter (DSC) and Dynamic Mechanical Analysis (DMA) were used to systematically characterize their structures and properties. The conclusions are showed as follows.1. The three-dimensional surface reconstruction of bone medical computerized tomography images was made based on the outer contours data of adjacent layer which had not destroyed its structure. The method was simple and convenient and the reconstruction was true to nature.2. The scaffolds porosity is enhanced with increasingβ-TCP content, and the porosity of the scaffold containing 67wt%β-TCP is up to 89% in the case of same porogen content. In addition, suitable addition ofβ-TCP can increase the dynamic storage modulus of the scaffolds, otherwise is not so, i.e. the dynamic storage modulus of the scaffold containing 50wt%β-TCP is up to 17.5MPa from the pure PLA's 4.4MPa; however, the dynamic storage modulus of the scaffold containing 67wt%β-TCP drops to 14.2MPa. Such a material containing 50wt% β-TCP is suitable for the bone tissue engineering scaffold, which obtained porosity to 89%, pore size morphology and dynamic storage modulus up to 17.5MPa and down to 16.5MPa after degradated for 20 days respectively.3. The initial modulus and dynamic storage modulus of single composite fibre are enhanced with addition ofβ-TCP in case of the same spinning condition. The fibres heat stability is increased along with the melting temperature, glass transition temperature and crystal temperature moving to high respectively. Such kind of composite fiber containing 10wt%β-TCP is valuable for applied with initial modulus to 4.8MPa, dynamic storage modulus to 951.2MPa and well spinning.