Sakamoto Yuki, Asaoka Kenzo, Kon Masayuki, Matsubara Toshio, Yoshida Kenichi
Department of Mechanical Engineering, Faculty of Engineering, The University of Tokushima, 2-1 Minamijosanjima-cho, Tokushima 770-8506, Japan.
Biomed Mater Eng. 2006;16(2):83-91.
The biological properties of a titanium (Ti) implant depend on its surface oxide film. The aims of the present study were to increase the specific surface oxide area on Ti using a porous structure and to study the relationship between the amount of apatite coating in simulated body fluid (SBF) and the actual surface area on titanium powders. Ti powders of 110 microm average diameter were sintered by spark plasma sintering. The sintered compacts had a porosity of 28%, a compressive elastic modulus of 7.9 GPa and an ultimate strength of 112 MPa. The compressive strength of the compacts was increased to 588 MPa by subsequent annealing in a vacuum furnace at 1000 degrees C for 24 h. The sintered compacts were treated with aqueous NaOH solution and subsequently heated at 600 degrees C. The pretreated compacts showed apatite crystal precipitation in SBF. The amounts of precipitates through the compacts were compared with those of the Ti plate substrates subjected to the same chemical pretreatment. It was confirmed that the amounts of precipitates through the compacts were more than one hundred times higher than those on the Ti plates. It was concluded that the metal porous compacts developed may be used as functional materials for immobilizing functional proteins and/or drugs, because the precipitated apatite can adsorbed these substances.
钛（Ti）植入物的生物学特性取决于其表面氧化膜。本研究的目的是利用多孔结构增加钛表面氧化膜的比表面积，并研究模拟体液（SBF）中磷灰石涂层的量与钛粉实际表面积之间的关系。通过放电等离子烧结法烧结平均直径为110微米的钛粉。烧结体的孔隙率为28%，压缩弹性模量为7.9 GPa，极限强度为112 MPa。通过随后在1000℃的真空炉中退火24小时，烧结体的抗压强度提高到588 MPa。将烧结体用氢氧化钠水溶液处理，随后在600℃加热。预处理后的烧结体在SBF中出现了磷灰石晶体沉淀。将通过烧结体的沉淀物量与经过相同化学预处理的钛板基材的沉淀物量进行比较。证实通过烧结体的沉淀物量比钛板上的沉淀物量高出一百多倍。得出的结论是，所开发的金属多孔烧结体可作为固定功能蛋白和/或药物的功能材料，因为沉淀的磷灰石可以吸附这些物质。
