Stupp S I, Hanson J A, Eurell J A, Ciegler G W, Johnson A
Department of Materials Science and Engineering, University of Illinois, Urbana-Champaign.
J Biomed Mater Res. 1993 Mar;27(3):301-11. doi: 10.1002/jbm.820270304.
This article reports on the in vivo testing of new artificial bone materials we have termed "organoapatites." These materials consist of mineral networks in which organic polymers are intimately dispersed by nucleation and growth of apatite crystals from a mother liquor containing the organic substances. Organoapatites were tested as implants in adult canine cortical bone for periods in the range from 12-35 weeks and fluorochromes were used in the model to investigate the kinetics of bone growth or repair. The analysis of histological samples was carried out using histomorphometric methods as well as fluorescence microscopy. Results showed excellent apposition of poly(amino acid) organoapatites with mineralized bone and fibrous encapsulation when a synthetic polyelectrolyte was the only organic component. This observation suggests that the molecularly dispersed organic dopant amounting to only 2-3% by weight of the microstructure can play a critical role in the tissue response to the implant. Relative to apatite controls, organoapatites were also found to have greater resistance to fragmentation in vivo and those containing amino acid units revealed interfacial bioerosion accompanied by regeneration of mineralized tissue. Design of organoapatite compositions and microstructures may therefore be useful in achieving the specific rate of biological response which is clinically desired.
本文报道了我们称之为“有机磷灰石”的新型人工骨材料的体内测试情况。这些材料由矿物网络组成，其中有机聚合物通过磷灰石晶体在含有有机物质的母液中形核和生长而紧密分散。有机磷灰石作为植入物在成年犬的皮质骨中进行了12至35周的测试，并在模型中使用荧光染料来研究骨生长或修复的动力学。使用组织形态计量学方法以及荧光显微镜对组织学样本进行分析。结果表明，当合成聚电解质是唯一的有机成分时，聚（氨基酸）有机磷灰石与矿化骨有良好的贴合以及纤维包裹。这一观察结果表明，占微观结构重量仅2 - 3%的分子分散有机掺杂剂在组织对植入物的反应中可能起关键作用。相对于磷灰石对照，还发现有机磷灰石在体内具有更大的抗破碎性，并且含有氨基酸单元的那些显示出界面生物侵蚀并伴有矿化组织的再生。因此，有机磷灰石成分和微观结构的设计可能有助于实现临床上所需的特定生物反应速率。
