Magnesium Are Closer To Those Of Natural Bone Than Ed Metallic Implants. Moreover, Magnesium Is Ess

Magnesium is an exceptionally lightweight metal. It is very close to the density of human bone(1.75g/cm3). While the elastic modulus and compressive yield strength of magnesium are closer to those of natural bone than is the case for other commonly used metallic implants. Moreover, magnesium is essential to human metabolism and is naturally found in bone tissue. Thus, it is projected that magnesium and its alloys be applied as lightweight, load bearing and good biocompatibility bone implants. However, the major drawbacks of magnesium in many applications are low corrosion resistance. So some surface treatments should be applied to meet the use of long-term implantation.Micro-arc oxidation (MAO) is a recently developed surface treatment technology under anodic oxidation. Through MAO, in-situ-grown ceramic coating is directly formed on the surface of metal, by which its corrosion resistance, wear resistance are greatly improved in industrial environment. In order to develop a new implant material, it is essential to understand its cytocompatibility with osteoblast during osseointegration.The objective of this study was to understand the effects of AZ91D Magnesium alloy modified by micro-arc oxidation on the adhesion,proliferation and alkaline phosphatase(ALP) activity of osteoblast , provide experimental basis for further study. PartⅠEffects of AZ91D magnesium alloy modified by micro-arc oxidation on the early adhesion of osteoblastObjective: To investigate the effects of AZ91D magnesium alloy modified by micro-arc oxidation on the early adhesion of human osteoblast-like MG63 cells in vitro.Metheds: AZ91D magnesium alloy modified by micro-arc oxidation ,The surface roughness and surface energy of the specimens were measured by the profilometer and the goniometer, SEM, EDS were used to test surface morphology and composition;Then MG63 cells were cultured on the surface of groups,the cell adhesion ratio was counted and the cell morphology was examined.The results was processed by SPSS 13.0 software package for one-way ANOVA.Results: The group A produced a layer of porous,rough oxide coating mainly composed of Mg,O,Si ,the surface roughness and surface energy of A were significantly higher than B(P<0.05),as the cultured time increased, the statistic results indicated that the cell adhesion ratio of A was significantly higher than B,C(P<0.05),SEM observation showed that the adhesion between cells and materials were pretty well after cultured 4h.Conclusions: The surface of AZ91D magnesium alloy modified by micro-arc oxidation possesses good biocompatibility,may increase original cell adhesion. PartⅡEffects of AZ91D magnesium alloy modified by micro-arc oxidation on the proliferation and activity of osteoblastObjective: To investigate the effects of AZ91D magnesium alloy modified by micro-arc oxidation on the proliferation and ALP activity of human osteoblast-like MG63 cells in vitro.Metheds: MG63 cells were cultured on the surface of each groups, cell proliferation was surveyed by MTT method at 1,4and 7d respectively,and ALP acivity was measured at 3d,7d .Results: Osteoblasts proliferation and ALP activity were higher on A surface than those on the other surface B ( P < 0. 05) .Conclusions: The AZ91D magnesium alloy modified by micro-arc oxidation possesses good cytocompatibility to osteoblast,may increase proliferation and ALP activity.