纯镁载聚乳酸-乙醇酸膜层的体内骨结合与降解行为

The Osseointegration and Degradation Behavior of Pure Magnesium PLGA Film in Vivo

目的:探讨纯镁载聚乳酸-乙醇酸共聚物[poly(lactic-co-glycolic acid),PLGA]对体内骨结合能力及降解速率的影响。方法:纯镁微弧氧化(micro arc oxidation,MAO)膜层为对照组(MAO组),纯镁载PLGA膜层为实验组(PLGA组),将2种涂层的镁钉植入家兔下颌骨内。分别于2、4、8和12周后分期处死家兔,在不脱钙的情况下截取载钉的下颌骨,并进行锥形束CT(CBCT)、微型CT(Micro-CT)、激光共聚焦显微镜和扫描电镜检测。结果:CBCT结果显示,PLGA组较MAO组低密度影像小,骨结合好;Micro-CT结果显示,PLGA组较MAO组降解速率低;扫描电镜和激光共聚焦显微镜可见PLGA组促新骨生成能力强于MAO组。结论:纯镁载PLGA膜层能够促进骨结合,并降低镁基体的降解速率。

Objective:To investigate the effect of pure magnesium loaded with poly(lactic-co-glycolic acid)(PLGA)on osseointegration capacity and degradation rate in vivo.Methods:Pure magnesium loaded with micro arc oxidation(MAO)coating was used as control group(MAO group)and pure magnesium loaded with PLGA coating was used as experimental group(PLGA group).They were implanted into the mandible of rabbits.After 2,4,8 and 12 weeks,the rabbits were killed,and the mandible was cut off without decalcification.Series examinations of scanning electron microscope(SEM),CBCT,Micro-CT,and laser confocal microscope were performed.Results:CBCT observation showed that PLGA group had smaller low-density images and better osseointegration than MAO group.Micro-CT results showed that the degradation rate of PLGA group was lower than that of MAO group.SEM and laser confocal microscope results showed that the ability of promoting new bone formation in PLGA group was stronger than that in MAO group.Conclusion:Pure magnesium loaded with PLGA film can promote osseointegration and reduce the degradation rate of magnesium matrix.