钛螺钉表面含硅二氧化钛纳米管层的体内成骨性能

In vivo osteogenic properties of silicon-incorporated titanium dioxide nanotubes on titanium screw surface

背景:目前假体及骨植入材料多采用钛及其合金材料,该类材料具有优越的力学特性及优良的抗腐蚀性,但其生物活性不足,很难与骨组织之间形成良好的化学键合。目的:在纯钛螺钉表面制备含硅二氧化钛纳米管涂层,观察其体内促成骨性能。方法:利用阳极氧化法在纯钛螺钉表面制备二氧化钛纳米管层(阳性对照组),采用等离子体浸没离子植入和沉积法将硅离子沉积在二氧化钛纳米管层表面(实验组),以纯钛螺钉作为阴性对照组,采用扫描电镜观察各组形貌。将3种螺钉分别植入SD大鼠股骨内,植入后2,4,6周取出股骨标本,进行生物力学检测;植入后6周进行免疫荧光分析。动物实验获得江南大学实验动物管理与动物福利伦理委员会批准。结果与结论:①扫描电镜显示,实验组与阳性对照组均可见均匀一致的双层纳米管阵列,两组间无明显差异;②螺钉植入后第2,4周,实验组的螺钉平均峰值拔出力显著高于阳性对照组、阴性对照组(P<0.05),且阳性对照组显著高于阴性对照组(P<0.05);第6周时,3组螺钉的平均峰值拔出力比较差异无显著性意义(P>0.05);③螺钉植入后第6周免疫荧光显示,阴性对照组螺钉周围几乎没有新生骨附着,实验组及阳性对照组的螺纹周围可见广泛的新生骨附着,其中实验组新骨生成最多;④结果表明,含硅二氧化钛纳米管层在大鼠体内可显著促进纯钛螺钉周围新生骨形成,并增加螺钉拔出力。

BACKGROUND:At present,titanium and its alloy materials are mostly used in prosthesis and bone implants.These materials have superior mechanical properties and excellent corrosion resistance,but their bioactivity is insufficient,so it is difficult to form a good chemical bond with bone tissue.OBJECTIVE:To prepare titanium dioxide nanotube coating containing silicon on the surface of pure titanium screw and observe its osteogenic properties in vivo.METHODS:Titanium dioxide nanotube layers were prepared on the surface of pure titanium screws by anodic oxidation method(positive control group).Silicon ions were deposited on the surface of titanium nanotube layers by plasma immersion ion implantation and deposition(experimental group).Pure titanium screws were used as negative control group.The morphology of each group was observed by scanning electron microscope.The three kinds of screws were implanted into the femur of SD rats.The femoral specimens were taken out at 2,4 and 6 weeks after implantation for biomechanical test,and immunofluorescence analysis was performed at 6 weeks after implantation.The animal experiment was approved by the Ethics Committee of Experimental Animal Management and Animal Welfare of Jiangnan University.RESULTS AND CONCLUSION:(1)Scanning electron microscopy showed that uniform double-layer nanotube arrays were observed in the experimental group and the positive control group,and there was no significant difference between the two groups.(2)At 2 and 4 weeks after screw implantation,the average peak pullout force of the experimental group was significantly higher than that of the positive control group and the negative control group(P<0.05),and the positive control group was significantly higher than the negative control group(P<0.05).At the sixth week,there was no significant difference in pullout force among the three groups(P>0.05).(3)Immunofluorescence showed that at 6 weeks after implantation,there was almost no new bone attachment around the screw in the negative control group,and extensive new bone attachment was observed around the screw thread in the experimental group and the positive control group,among which the new bone formation was the most in the experimental group.(4)The results showed that the silicon dioxide titanium nanotube layer could significantly promote the formation of new bone around the pure titanium screw and increase the pullout force of screws.