钛合金表面微粗糙化对成骨细胞黏附及增殖行为的影响

Effect of Surface Microroughening of Titanium Alloy on Osteoblast Adhesion and Proliferation Behavior

采用表面机械研磨(SMAT)法对Ti-25Nb-3Mo-3Zr-2Sn(TLM)钛合金处理15min,而后将处理前后的钛合金样品与成骨细胞共培养1h、24h。采用X射线衍射(XRD)、光学显微镜(OM)、透射电镜(TEM)、扫描电镜(SEM)、电子能谱(EDX)及激光共聚焦显微镜(CLSM)对处理前后样品表面的结构进行了分析,结果显示SMAT处理不会改变TLM钛合金的物相、晶粒尺度及化学组成,处理前后物相均由单一的β相组成,晶粒尺寸均在10~20μm且没有引入新的杂质元素,但SMAT处理会改变TLM钛合金的表面粗糙度,处理前的样品表面平整,平均粗糙度Ra为(0.2±0.03)μm,而处理后的样品表面坑洼不平,平均粗糙度Ra增至(2.6±0.4)μm。随后的细胞实验结果显示,对比SMAT处理前,成骨细胞在处理后的微粗糙表面铺展得更为充分,增殖得更加迅速。研究表明,SMAT处理可以改善TLM钛合金表面的成骨细胞生长环境,从而为开发出更符合临床应用的钛金属种植体提供新的思路。

Ti-25Nb-3Mo-3Zr-2Sn （TLM） titanium alloy was treated via surface mechanical attrition treatment （SMAT） for 15 rain in this paper, after which the treated and untreated titanium alloy samples were respectively cultured with osteoblast cells for 1 h and 24 h. XRD, OM, TEM, SEM, EDX and CLSM were adopted to analyze the structure of the samples, and the obtained results revealed that SMAT process did not alter the phase composition, grain size and chemical composition of TLM alloy. Both the treated and untreated titanium alloys were composed of the same solely ② phase, in the same grain size of about 10-20μm and without new- ly-brought impurity elements. However, this treatment would alter the surface roughness of TI.M alloy. The untreated sample pos- sessed a smooth surface with a roughness value Ra of about （0. 2±0. 03）μm, whereas the treated surface owed an uneven surface with a roughness value Ra of about （2. 6 ± 0. 4） μm. The subsequent cellular experiment showed that the seeded osteoblasts on SMAT-treated surface spread much wider and proliferated more rapidly compared with the untreated surface. Our study suggests that SMAT could improve the living condition of osteoblast on TLM alloy surface, thus providing a promising means for the design of more potential biomedical titanium implants used on clinic.