TiO2喷砂酸蚀处理对钛片表面氧化膜及成骨细胞生长影响的研究

目的研究纯钛钛片经喷砂及喷砂酸蚀处理后，表面氧化膜金相结构和化学成分的变化及对成骨细胞黏附和生长特性的影响。方法将直径为15 mm、厚度为1 mm的纯钛钛片分4组进行表面处理：1）机械打磨组（S0）；2）喷砂组（SB）；3）喷砂酸蚀1组（SLA1）；4）喷砂酸蚀2组（SLA2）。采用电子探针分析仪及X射线衍射仪检测4组钛片表面氧化膜的厚度、化学成分以及金相结构，扫描电镜观察其表面微观形态。而后将成骨细胞培养于4组钛片表面，采用MTT法分析比较4组钛片表面对成骨细胞黏附率以及增殖率的影响。结果与S0组相比，SB、SLA1、SLA2组的粗糙度明显增大（P<0.05）。SB、SLA1、SLA2组间表面平均粗糙度差异无统计学意义（P>0.05）。酸蚀处理使喷砂形成的氧化膜变薄，密度减低，且结构发生改变：原有的金红石型TiO2峰消失，锐钛矿型TiO2减少。在表面平均粗糙度相同条件下，SB组钛片表面氧化膜均匀致密，有利于成骨细胞早期的黏附和增殖。结论喷砂和喷砂酸蚀处理均增加了钛片表面的粗糙度，有利于成骨细胞的黏附和增殖，但酸蚀使TiO2喷砂表面的氧化膜层变薄，在平均粗糙度不变的情况下，单纯喷砂表面成骨细胞的黏附和增殖优于喷砂酸蚀处理表面。

Effects of TiO2 blasted and acid-etched titanium surfaces on oxide-film and osteoblast

Objective To study the effects of TiO2 blasted and acid-etched surfaces of cp-titanium on changing composition of oxide-film and attachment and proliferation of osteoblasts in vitro. Methods cp-titanium discs were prepared and divided into 4 groups:TiO2 blasted(SB), sandblasted and acid-etching(SLA1 and SLA2) and machine-polished surface(S0). Scanning electron microscopy(SEM), X-ray diffraction(XRD) and electron probe microanalysis(EPMA) were used to test surface morphology and composition of oxide-film. Osteoblasts were cultured on the titanium surface of 4 groups. MTT assay was used to measure the attachment and proliferation. Results In regard to surface roughness, average roughness for SB, SLA1 and SLA2 was obviously higher than S0. Oxygen ratio increased on SB,contrarily, it decreased on SLA. A mixture of anatase and rutile-type crystals were observed in the SB. Smaller anatase were observed in the SLA1 and SLA2. The oxide thickness on SLA surface was thiner than that on the SB surface. After 1, 4, 24 hours' culture, the number of osteoblast attachment on SB surfaces was the highest(P<0.05). The number of cells osteoblast proliferation was the highest on SB after 1, 3, 5 and 7 days' culture(P<0.05). Conclusion The thickness and chemical composition of oxide film play an important role in osteoblast attachment and proliferation at the same roughness surface. It is concluded that osteoblast attachment and proliferation are better on SB surfaces than on SLA1 and SLA2 surfaces.