一种可注射自固化含锶复合胶原磷酸钙骨水泥的结构和性能

背景:骨科学界正致力于磷酸钙骨水泥的改性研究,通过向磷酸钙骨水泥中加入不同的添加剂,包括固化促进剂、增塑剂、抗水,血溶剂、致孔剂、增强剂,或是将生物活性物质或药物复合到磷酸钙骨水泥中,以提高其理化和生物学性能是目前该领域的研究热点.目的:了解一种新型可注射可降解的磷酸钙骨水泥的理化性能.设计、时间及地点:重复测量试验,于2008-12/2009-05在华南理工大学材料学院国家重点实验室完成.材料:采用部分结晶的磷酸钙,部分结晶的磷酸锶和二水磷酸氢钙,添加改性淀粉、Ⅰ型胶原制备了新型可注射自固化磷酸钙骨水泥.方法:采用X'Pert Pro型X射线衍射仪对磷酸钙骨水泥固化体进行相分析.采用HITA2-GHIH-800型透射/扫描电子显微镜对磷酸钙骨水泥固化体的形貌进行观察.用维卡仪根据美国材料与试验协会A S TM C190203标准进行凝结时间的测试.使用Instron 5567型万能电子材料试验机来测试固化样品的抗压强度.用注射器测试材料的可注射性,针头内径为1.6 mm.通过浸泡摇动定性测试材料的抗溃散性.主要观察指标:①骨水泥水化产物的相组成和显微结构.②骨水泥的凝固时间、可注射性和抗压强度.③骨水泥的抗溃散性.结果:研究表明该材料具备优良的可注射性能;添加改性淀粉显著的改善了骨水泥的抗溃散性.随着骨水泥液固比的增大,骨水泥的抗压强度下降,当骨水泥的液固比为0.3时,骨水泥的抗压强度为(48.0±2.3)MPa,当骨水泥的液固比为0.6时,骨水泥的抗压强度下降为(21.0±2.5)MPa.骨水泥的水化产物为类骨羟基磷灰石结晶,从X射线衍射图谱还可以看出,因骨水泥的水化不完全,基线水平波动较大,说明了在充分水化的条件下,骨水泥的压缩强度还能进一步提高.结论:制备的可注射含锶复合胶原磷酸钙骨水泥符合人体生物力学强度,能满足手术条件要求.

Structure and performance of injectable strontium-contained collagen calcium phosphate cement

BACKGROUND: Orthopedic academics are committed to the modification of calcium phosphate cement (CPC) by adding different additives, including the promotion of curing agents, plasticizers, anti-water blood solvent, porogen, enhancer, or biological activity substance or drug compound to the CPC in order to enhance its physical and chemical and biological properties which is a research hotspot in the field. OBJECTIVE: To investigate the physical and chemical characteristics of a biodegradable injectable CPC. DESIGN, TIME AND SETTING: Duplicated testing study was performed at the National Key Laboratory, College of Materials, South China University of Technology from December 2008 to May 2009. MATERIALS: Calcium phosphate with partial crystallization and strontium phosphate and calcium hydrogen phosphate dehydrate with partial crystallization were added with modified starch and type I collagen to prepare a new type of self-injectable CPC. METHODS: CPC phase was analyzed using X'Pert Pro X-ray diffractometer; CPC morphology was observed using HITA2 -CHIH-800 transmission/scanning electron microscope; setting-up time was tested using Vicat apparatus according to A S TM C190203 standard; compressive strength was measured using Instron 5567 omnipotent electron apparatus; syringeability was detected using syringe apparatus with 1.6 mm of inside diameter; collapsibility was tested using soaking-shaking quantitative materials. MAIN OUTCOME MEASURES: Phase component and microstructure of CPC products, setting-up time, syringeability, compressive strength, and collapsibility. RESULTS: The material coul be injected with an excellent performance, and the modified starch significantly improved the resistance of bone cement collapsibility. As the bone cement liquid-solid ratio increased, the compressive strength of cement decreased. When the bone cement liquid-solid ratio was 0.3, the compressive strength for cement was (48.0±2.3) MPa when the bone cement liquid-solid ratio was 0.6, the compressive strength of bone cement reduced to (21,0±2.5) MPa. Hydration product of cement-like bone hydroxyapatite crystallization also could be seen from the X-ray diffraction, due to the hydration of-cement was not complete, a baseline level of volatile explained fully hydrated conditions, suggesting that the bone cement could farther improve the compression strength. CONCLUSION: Developed an injectable strontium-contained collagen CPC is coincidence with the biomechanical strength of the human body and meets the requirements of the operation conditions.