微创医学

目的利用两种粒径的聚甲基丙烯酸甲酯（ PMMA）微球作为微球工具以不同的粒径比和质量比加入磷酸钙骨水泥（ CPC）后观察其对复合物孔隙率的影响。方法使用50 μm/15 μm PMMA微球、100 μm/50 μm PMMA微球和20 μm/15 μm PMMA微球三种粒径组合方式（微球占复合物的体积比均为50%），每种组合中微球的质量比分别为2 ∶8、3 ∶7、4 ∶6、5 ∶5、6 ∶4、7 ∶3和8 ∶2，高温煅烧后用密度法计算磷酸钙骨水泥的孔隙率。结果50 μm/15 μm PMMA微球质量比为2 ∶8、3 ∶7、4 ∶6、5 ∶5、6 ∶4、7 ∶3和8 ∶2时CPC复合物孔隙率分别为（70.9±1.2）%、（70.0±0.6）%、（67.9±0.7）%、（71.2±0.9）%、（68.4±0.8）%、（70.5±0.8）%、（71.2±1.8）%；100 μm/50 μm PMMA微球质量比为2 ∶8、3 ∶7、4 ∶6、5 ∶5、6 ∶4、7 ∶3和8 ∶2时CPC复合物孔隙率分别为（70.9±1.2）%、（71.3±2.6）%、（69.6±2.4）%、（71.1±1.5）%、（68.8±0.9）%、（69.1±1.5）%、（69.9±1.9）%；20 μm/15 μm PMMA微球质量比为2 ∶8、3 ∶7、4 ∶6、5 ∶5、6 ∶4、7 ∶3和8 ∶2时CPC复合物孔隙率分别为（76.7±2.9）%、（72.7±1.2）%、（70.7±0.7）%、（69.7±1.1）%、（70.8±2.1）%、（72.5±2.5）%、（66.9±1.4）%。结论在磷酸钙骨水泥中添加相同体积的两种不同粒径微球，孔隙率会随着粒径比和质量比的变化而变化。

ObjectiveTo use two different particle size of Polymeric Methyl Methacrylate（PMMA） microspheres as a tool and observe the influence of porosity of complex after adding different quality ratio tocalcium phosphate cement (CPC). MethodsAdding 50 μm/15 μm PMMA microspheres, 100 μm/50 μm PMMA microspheres and 20 μm/15 μm PMMA microspheres (microspheres accounted for the volume of the complexes were 50%) to CPC, and each combination microspheres quality ratio were 2 ∶8， 3 ∶7， 4 ∶6， 5 ∶5， 6 ∶4, 7 ∶3 and 8 ∶2, respectively. ResultsIf the 50 μm /15μm PMMA microspheres mass ratio were 2 ∶8, 3 ∶7, 4 ∶6, 5 ∶5, 6 ∶4, 7 ∶3 and 8 ∶2,the CPC composite porosity were (70.9±1.2)%, (70.0±0.6)%, (67.9±0.7)%, (71.2±0.9)%, (68.4±0.8)%, (70.5±0.8)%, (71.2±1.8)%；If the 100 μm/50 μm PMMA microspheres mass ratio were 2 ∶8, 3 ∶7, 4 ∶6, 5 ∶5, 6 ∶4, 7 ∶3 and 8 ∶2,the CPC composite porosity were(70.9±1.2)%, (71.3±2.6)%, (69.6±2.4)%, (71.1±1.5)%, (68.8±0.9)%, (69.1±1.5)%, (69.9±1.9)%；If the 20 μm/15 μm PMMA microspheres mass ratio were 2 ∶8, 3 ∶7, 4 ∶6, 5 ∶5, 6 ∶4, 7 ∶3 and 8 ∶2,the CPC composite porosity were(76.7±2.9)%, (72.7±1.2)%, (70.7±0.7)%, (69.7±1.1)%, (70.8±2.1)%, (72.5±2.5)%, (66.9±1.4)%. ConclusionWhen adding two kinds of microspheres with the same volume in the calcium phosphate cement ,the porosity changes with the ratio of the particle size and the mass ratio.