Abstract Magnesium-based metals are promising for biomedical use for its biodegradation characteristic. However, its rapid degradation in physiological environment impedes its application. Oxides coating is a widely-used form of surface modification to improve the corrosion resistance of biomaterials. In this study, we systematically compared two oxides coatings, steam oxidation (SO) and micro-arc oxidation (MAO), in controlling degradation and improving the biocompatibility of pure magnesium in vitro and in vivo . The addition of both coatings was found to reduce the degradation rate of magnesium in vitro at the early stage, but the corrosion behavior became severe with longer immersion time in all the groups. Unfortunately, all the coated and uncoated materials were found undermining the adhesion and proliferation of MC3T3-E1 cells in vitro , even at the first day of culture. In terms of in-vivo circumstance, the Mg-MAO group showed satisfying biocompatibility compared with pure Mg and Mg-SO, as is evidenced by radiographic results and histological analysis. Little corrosion was found, and more newly formed bone was observed in the animal model. These data suggest that the characteristic of in-vivo circumstance have considerable impacts on the degradation and bone integration process.

中文翻译：

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镁-MAO 的降解性和生物相容性：体外和体内结果的一致性和矛盾

摘要 镁基金属由于其生物降解特性，在生物医学领域具有广阔的应用前景。然而，其在生理环境中的快速降解阻碍了其应用。氧化物涂层是一种广泛使用的表面改性形式，以提高生物材料的耐腐蚀性。在这项研究中，我们系统地比较了两种氧化物涂层，蒸汽氧化 (SO) 和微弧氧化 (MAO)，在控制降解和提高纯镁的体外和体内生物相容性方面。发现两种涂层的添加在早期降低了体外镁的降解率，但随着浸泡时间的延长，所有组的腐蚀行为变得严重。不幸的是，发现所有有涂层和无涂层的材料都破坏了体外 MC3T3-E1 细胞的粘附和增殖，即使在文化的第一天。在体内环境方面，与纯 Mg 和 Mg-SO 相比，Mg-MAO 组显示出令人满意的生物相容性，放射学结果和组织学分析证明了这一点。几乎没有发现腐蚀，在动物模型中观察到更多新形成的骨骼。这些数据表明，体内环境的特征对降解和骨整合过程有相当大的影响。