The development of taylor-made materials with biomedical function.

多孔钛在生物医学领域的应用是近年来发展起来的。然而，很难制造出各种形状，因为它们是在模具中形成和烧结的。在本研究中，研制了一种钛粉和镶嵌蜡粘结剂的混合物，用于无模具成型和烧结。研究了钛粉与石蜡粘结剂(石蜡的质量比为10%)在70℃下的混合成型工艺、烧结后的尺寸变化以及多孔钛的物理、力学和生物性能。脱粘后，在1100℃的Ar气氛中进行无模烧结。烧结时间分别为1、5、10h。测试了材料的收缩、气孔率、吸水率和力学性能。为了检测标本的生物活性，进行了成骨细胞样细胞的培养。进行了三种类型的钛试件的植入试验；商业多孔钛作为对照，多孔钛…更多的是由我们的工艺生产的多孔钛，而我们的工艺饱和的多孔钛是一种促进骨形成的药物。成骨的组织学观察和骨接触比测量表明，随着烧结时间的延长，材料的抗弯强度、抗压强度和弹性模量均有所增加。强度高于皮质骨，弹性模数与皮质骨相近。随着掺量的增加，干缩率增大，气孔率和吸水率降低。烧结时间对材料力学性能和吸收率的影响主要是由于烧结过程中气孔率降低所致。成骨细胞样细胞生长良好，均匀贴附于所有标本表面。本工艺制备的多孔钛的骨接触率明显高于对照组。然而，这种药物的效果并不显著。相反，加药后试件周围的新骨厚度明显大于未加药的试件周围的新骨厚度，该工艺的高成形性对骨替代单元的形成和加工具有明显的优势。与皮质骨相比，多孔钛的强度并不逊色，弹性模量值与皮质骨相近。多孔钛表现出足够的生物活性和骨传导性，可用于生物医学应用，并具有良好的DDS功能。较少

Porous titanium has been developing recently for biomedical application. It is difficult, however, to make a various shape, since they are formed and sintered in a mold. In this study, a mixture of titanium powder and an inlay wax binder was developed for moldless forming and sintering without any mold. The formability of the mixture, the dimensional change after sintering, and the physical, mechanical and biological properties of the sintered porous titanium produced were evaluated.Mixture of Ti powder and wax binder (mixing ratio of wax was 10 mass%) was formed manually at 70℃. After debindering, the specimen was sintered in Ar at 1100℃ without any mold. The sintering times were 1, 5, and 10 hours. The shrinkage, porosity, absorption rate and mechanical property were measured. To examine the bioactivity of the specimen, osteoblast-like cells were cultured. Implantation tests of three types of titanium specimen were performed ; commercial porous titanium as a control, porous titanium … More produced by our process, and the porous titanium by our process saturated by a drug enhancing bone formation. Histological observations of osteogenesis and bone contact ratio measurement were performed.The bending strength, compression strength and elastic modulus were increased with increasing sintering time. The strengths were higher than that of cortical bone and the modulus was similar to that of cortical bone. The shrinkage was increased with it, while the porosity and absorption rate were decreased with it. These effects of sintering time on mechanical properties and absorption rate were mainly due to the reduction of porosity with progress of sintering. The osteoblast-like cells grew well and evenly adhered on the surface of all specimens. The bone contact ratios of porous titanium by our process were significantly higher than that of control. However, the effect of the drug was not significant. On the contrary, the thickness of new bone around the specimen with the drug was significantly larger than that without drug.The high formability of the process in this research showed a clear advantage for forming and processing of bone substitution units. The porous titanium showed no inferiority in strength compared with the cortical bone and similar elastic modulus with it. The porous titanium demonstrated sufficient bioactivity and bone conductivity for biomedical applications, and good functionality for DDS. Less