ABSTRACT
[Objective]To study the mechanism of magnesium alloy degradation and bone formation at the bone-implant interface after implanting a magnesium alloy into rat femur.[Method]SD rats femur were filled with magnesium alloy stick.Nine weeks later,animals were killed and femur were retrieved.Systematic investigations on the surface morphology,composition,structure of bone-implant were performed by means of metallurgical microscope,scanning electron microscopy(SEM),and energy dispersive spectrum(EDS).Decalcified sections were prepared,and histologic examination was carried out.[Result]The bone response happened both on the surface of surrounding bone and the surface of magnesium alloy degradation layer while magnesium alloy degradating in rat femur.It was formed three layers at the interface of bone-implant: the metal layer,the degradation layer,and the new bone layer.Discontinuity connective tissue could be seen on the new bone layer but no inflammatory cells were found.[Conclusion]The new bone response at the interface of bone-implant is consistent with normal bone tissue.Magnesium alloys have good characters of degradation ability,osteogenesis ability,and histocompatibility.And the rate of degradation is corresponding to the rate of new bone formation.
ABSTRACT
[Objective]To observe mouse osteoblasts vitality,histomorphology and growing development in vitro co-culture combined with magnesium alloys,confirm the biocompatibility of magnesium alloys and osteoblasts,and try to find out the possibility of magnesium alloys to be a new type of bone surgery implant material.[Method]Mouse osteoblasts were checked by Gomori and Von kossa stained,cultured and developed in vitro.Then the osteoblasts were mixed with magnesium alloys in a cell density of 3?104/ml.After 24、48、72 hours co-culture,the surface of magnesium alloys were observed by scanning electron microscopy(SEM) and confocal microscopy to find the change of osteoblasts.[Result]After culture in vitro,the osteoblasts well developed,and expressed stable character.After co-culture with magnesium alloys,the cells adhered and proliferated on the surface of alloys very well from SEM and confocal microscopy observation,which showed the osteoblasts had great activity and reproduce capability.[Conclusion]Magnesium alloys showed good biocompatibility and bone conduction capability with mouse osteoblasts,so the magnesium alloy is very possible to be a new type of bone surgery implant material.
ABSTRACT
0.05).RGR showed that the toxicity level of magnesium alloys was 0.And there was no significant abnormality found in biochemical indicators and pathological analysis after inplant in vivo.[Conclusion]Magnesium alloys showed good biocompatibility to L929 mouse fibroblasts,and had no cacoethic effect to test animals,so the magnesium alloys is possible to be a new type and potential of bone surgery implant materials.