In:
Journal of Biomedical Materials Research Part B: Applied Biomaterials, Wiley, Vol. 100B, No. 8 ( 2012-11), p. 2251-2260
Abstract:
We elucidated the in vivo corrosion mechanism of the biodegradable alloy Mg–10 wt % Ca in rat femoral condyle through transmission electron microscope observations assisted by focused ion beam technique. The alloy consists of a primary Mg phase and a three‐dimensional lamellar network of Mg and Mg 2 Ca. We found that the Mg 2 Ca is rapidly corroded by interdiffusion of Ca and O, leading to a structural change from lamellar network to nanocrystalline MgO. In contrast to the fast corrosion rate of the lamellar structure, the primary Mg phase slowly changes into nanocrystalline MgO through surface corrosion by O supplied along the lamellar networks. The rapid interdiffusion induces an inhomogeneous Ca distribution and interestingly leads to the formation of a transient CaO phase, which acts as a selective leaching path for Ca. In addition, the outgoing Ca with P from body fluids forms needle‐type calcium phosphates similar to hydroxyl apatite at interior and surface of the implant, providing an active biological environment for bone mineralization. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
Type of Medium:
Online Resource
ISSN:
1552-4973
,
1552-4981
DOI:
10.1002/jbm.b.v100b.8
Language:
English
Publisher:
Wiley
Publication Date:
2012
detail.hit.zdb_id:
2130917-6
SSG:
12
