低结晶性碳酸磷灰石团块骨移植材料的合成及性能

背景：作为优良的生物吸收性骨移植材料,碳酸磷灰石团块通常通过烧结过程来制备,然而,烧结过程中造成的碳酸含量流失将导致其生物吸收性明显下降,低于生体骨,从而影响新骨的生成。目的：合成低结晶性碳酸磷灰石团块作为骨移植材料并研究其性能。方法：通过氢氧化钙团块的碳酸化生成碳酸钙团块,浸泡在60℃、1mol/L磷酸二氢铵盐溶液中1-14d,并对各样本通过径向抗拉强度测试进行生物力学性能分析,通过X射线衍射分析、红外吸收光谱测定、扫描电子显微镜观察与碳酸含量、钙磷元素测定等进行理化性能分析。结果与结论：结果发现,经过磷酸二氢铵盐溶液处理14d后,碳酸钙已几乎完全转化成为结晶度较低的B型碳酸磷灰石;最终生成物的径向抗拉强度值为（10.27±1.08）MPa,满足骨缺损移植材料的机械强度要求;其碳酸含量为（4.80±0.50）%,与生体骨的碳酸含量极其接近;钙磷摩尔比为1.63±0.01,提示为贫钙型碳酸磷灰石。结果证实,实验将碳酸钙团块浸泡在60℃,1mol/L的磷酸二氢铵盐溶液中,成功合成了具有足够强度的低结晶性B型碳酸磷灰石团块,方法简单可行。

Fabrication and properties of Iow-crystallinity carbonate apatite monolith bone graft

BACKGROUND： As a good candidate for bioresorbable bone graft, carbonate apatite monolith can be prepared by sintering procedure; however, sintering can cause carbonate loss and result in a much lower rate of biodegradation compared to the human bone, thereby influencing the formation of new bone. OBJECTIVE： To fabricate Iow-crystallinity carbonate apatite monolith as bone graft and test its properties. METHODS： Calcium carbonate monolith prepared by carbonation of Ca（OH）2 monolith was treated in 1 mol/L ammonium dihydrogen phosphate solution at 60 ~C up to 14 days. Diametral tensile strength was examined for biomechanical properties; X-ray diffraction analysis, Fourier transform infrared spectroscopy, scanning electron microscope observation and chemical analyses （carbonate, calcium and phosphate content） were also performed for physical and chemical properties. RESULTS AND CONCLUSION： The calcium carbonate completely transformed into Iow-crystallinity B-type carbonate apatite after treated for 14 days. Diametral tensile strength of the final product was （10.27＋1.08） MPa, which is adequate as a reconstruction material for bone defect. The carbonate content was （4.80_＋0.50）%, similar to that of the nature bone. The molar Ca/P was 1.63＋0.01, indicating the Ca-deficient carbonate apatite is obtained. The present method allows an easy fabrication of Iow-crystallinity B-type carbonate apatite block with adequate strength and without sintering process.