基于三维打印的磷酸三钙骨组织工程支架烧结工艺研究

磷酸三钙(TCP)是构建骨组织工程支架常用的生物陶瓷材料。三维(3D)打印的TCP支架具有精确可控的孔隙结构,但存在力学性能不足的问题。由于烧结工艺对生物陶瓷支架力学性能的影响至关重要,本文详细探讨了不同烧结温度对3D打印TCP支架的力学性能的影响,测试了不同烧结温度制备的支架的表观形貌、质量和体积收缩率、孔隙率、力学性能以及降解性能。结果表明,当烧结温度为1150℃时,晶粒生长充分、气孔最少,支架具有最大的体积收缩率、最小的孔隙率以及最优的力学性能,压缩模量和抗压强度可以分别达到(100.08±18.6)MPa和(6.52±0.84)MPa,能够满足人体松质骨力学强度的要求。此外,与其他烧结温度下制备的支架相比,1150℃下烧结制备的支架在酸性环境中降解最慢,进一步说明其在长期植入时具有更佳的力学稳定性。该支架可支持骨髓间充质干细胞(BMSCs)黏附和快速增殖,具有良好的生物相容性。综上,本文优化了3D打印TCP支架的烧结工艺,提高了其力学性能,为其作为承重骨的应用奠定了基础。

Research on sintering process of tricalcium phosphate bone tissue engineering scaffold based on three-dimensional printing

Tricalcium phosphate(TCP)is one of the most widely used bioceramics for constructing bone tissue engineering scaffold.The three-dimensional(3D)printed TCP scaffold has precise and controllable pore structure,while with the limitation of insufficient mechanical properties.In this study,we investigated the effect of sintering temperature on the mechanical properties of 3D-printed TCP scaffolds in detail,due to the important role of the sintering process on the mechanical properties of bioceramic scaffolds.The morphology,mass and volume shrinkage,porosity,mechanical properties and degradation property of the scaffold was studied.The results showed that the scaffold sintered at 1150℃had the maximum volume shrinkage,the minimum porosity and optimal mechanical strength,with the compressive strength of(6.52±0.84)MPa and the compressive modulus of(100.08±18.6)MPa,which could meet the requirements of human cancellous bone.In addition,the 1150℃sintered scaffold degraded most slowly in the acidic environment compared to the scaffolds sintered at the other temperatures,demonstrating its optimal mechanical stability over longterm implantation.The scaffold can support bone mesenchymal stem cells(BMSCs)adherence and rapid proliferation and has good biocompatibility.In summary,this paper optimizes the sintering process of 3D printed TCP scaffold and improves its mechanical properties,which lays a foundation for its application as a load-bearing bone.