“脑回形(cortex-like)”微弧氧化膜钛种植体成骨的Micro-CT分析

Micro-CT Analysis of Osseointegration of Cortex-like Titania Implant Coatings with Micro-arc Oxidation

目的:利用Micro-CT评价"大脑皮质"(cortex-like)形貌的二氧化钛膜层在初始稳定性和继发稳定性阶段的骨-种植体结合的能力。方法:实验组MAO(cortex-like)为"大脑皮质"形貌种植体,对照组SLA为具有同等规格的SLA形貌的种植体,共计36颗,通过扫描电镜(SEM)等对材料表面进行表征,随机植入18只新西兰雄性兔的股骨髁部,分别于4周和8周处死取样,所得标本行Micro-CT扫描重建,分析MAO和SLA种植体表面的骨结合状况以及的骨小梁形态学参数。结果:类"大脑皮质"形貌氧化层由微米级沟槽和纳米级孔洞组成,沟槽相互交通,接触角(6.9±1.14)°,Micro-CT检测可见:随着骨结合时间的延长,骨体积分数(BV/TV)、骨小梁数量(Tb.N)、厚度(Tb.Th)、连接密度增加(Conn.Dn)均增加,结构模型指数(SMI)、骨小梁分离度(Tb.Sp)下降,第4周时,BV/TV,SMI组间比较差异存在统计学意义(P<0.05),第8周时,BV/TV、Tb.N、Tb.Sp、Conn.Dn值组间比较差异存在统计学意义(P<0.05),MAO高于SLA组。结论:"大脑皮质"(cortex-like)形貌的二氧化钛、具有双微层结构膜层,能促进种植体的骨结合的提升,是一种良好的种植体改性方法。

Objective：To assess the osseointegration of porous titania（TiO2）coating with a novel cortex-like morphology by micro-CT.Methods：Cortex-like morphology Ti surface was produced by MAO,and SLA surface was used as control.The surface features were evaluated by scanning electron microscope（SEM）and contact Angle.Thirty-six threaded implants were placed in the femoral condyles of 18 male New Zealand White rabbits.Trabecular bone morphology parameters were analyzed after implantation 4 weeks and 8 weeks by Micro-CT.Results：Morphology microstructure of MAO cortex-like was composed of microscale and nanoscale structure,with better wettability and contact Angle（6.9±1.14）°.Along with the time of bone healing,the BV/TV,Tb.N,Tb.Th and Conn.Dn were increased,while SMI and Tb.Sp were decreased.At 4th week,statistical significances were detected in BV/TV and SMI（P〈0.05）.At 8th week,statistical significances were detected in BV/TV,Tb.N,Tb.Sp and Conn.Dn（P〈0.05）.Cortex-like morphology exhibited more continuous bone apposition.Conclusion：The cortex-like morphology of titanium with microscale and nanoscale topologic structure can improve the osseointegration of Ti implant and has good biocompatibility.