Calcium phosphate cement (CPC) modified with native and pregelatinized normal corn and waxy maize starches was studied. Effects of starch pregelatinization and starch type on the physicochemical properties of CPC were investigated. CPC modified with pregelatinized normal corn starch (CPB-PNC) or pregelatinized waxy maize starch (CPB-PW) was evaluated by two vertebral fracture surgical models in vitro. Both granular and pregelatinized starches significantly improved the setting times and injectability of CPC, but only the pregelatinized starches improved the anti-collapsibility and compressive strength of CPC significantly. CPB-PW, whose micro-structure was compact and uniform, showed the best physicochemical properties. Addition of starch did not inhibit the hydro-reaction of CPC. Unmodified CPC had very poor dispersibility and could not apply in the tests of the surgical models. Pregelatinized starch especially waxy maize starch improved the dispersibility of CPC and showed good dispersion area, volume, improved pull-out force and maximum torque in the Sawbones sponge model. Similarly, in the minimally invasive kyphoplasty model, CPB-PNC and CPB-PW could disperse in the osteoporotic sheep vertebrae and improve the compressive strength of the sheep vertebral body. In conclusion, starch pregelatinization and starch botanical source affect the physicochemical properties of CPC significantly. Bone cements modified by different starches also performed differently in surgical models for osteoporotic vertebral fracture. Pregelatinized waxy maize starch may be a better candidate for CPC modification comparing to the pregelatinized normal corn starch.

中文翻译：

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磷酸钙基复合水泥：淀粉类型和淀粉预糊化对其体外椎体骨折手术模型的理化性质和性能的影响

研究了用天然和预胶化的普通玉米和蜡质玉米淀粉改性的磷酸钙水泥 (CPC)。考察了淀粉预糊化和淀粉类型对CPC理化性质的影响。用两种椎体骨折手术模型体外评价预糊化普通玉米淀粉（CPB-PNC）或预糊化糯玉米淀粉（CPB-PW）改性的CPC. 颗粒状淀粉和预糊化淀粉均显着提高了CPC的凝固时间和可注射性，但只有预糊化淀粉显着提高了CPC的抗塌陷性和抗压强度。CPB-PW的微观结构致密均匀，理化性能最好。添加淀粉不抑制CPC的加氢反应。未改性的CPC分散性很差，不能用于手术模型的测试。预糊化淀粉特别是蜡质玉米淀粉提高了CPC的分散性，在Sawbones海绵模型中表现出良好的分散面积、体积、提高的拉拔力和最大扭矩。同样，在微创后凸成形术模型中，CPB-PNC和CPB-PW可以分散在骨质疏松的羊椎骨中，提高羊椎体的抗压强度。综上所述，淀粉预糊化和淀粉植物来源对CPC的理化性质影响显着。不同淀粉改性的骨水泥在骨质疏松性椎体骨折手术模型中的表现也不同。与预糊化的普通玉米淀粉相比，预糊化的糯玉米淀粉可能是更好的 CPC 改性候选者。