Zinc shows great promise as a bio-degradable metal. Our early in vivo investigations implanting pure zinc wires into the abdominal aorta of Sprague-Dawley rats revealed that metallic zinc does not promote restenotic responses and may suppress the activities of inflammatory and smooth muscle cells. However, the low tensile strength of zinc remains a major concern.
View Article and Find Full Text PDFMagnesium alloys are promising implant materials for use in orthopaedic applications. In the present study, screws made of the Mg-alloy ZEK100 (n = 12) were implanted in rabbit tibiae for four and six weeks, respectively. For degradation analysis, in vivo µ-computed tomography (µCT), a determination of the weight changes and SEM/EDX examinations of the screws were performed.
View Article and Find Full Text PDFMater Sci Eng C Mater Biol Appl
July 2013
The present work aimed to investigate the influence of acetone and formalin as well as the duration and type of storage on magnesium based implants by means of microscopic, μ-computed tomographic, scanning electron microscopic, EDX and metallographic investigations. In contrast to storing in acetone, storage in formalin led to an increase in surface to volume ratio, and a decrease of the volume and the density. The various types of storage exerted no differing effects on the implants but with increasing storage duration, a spreading of oxygen rich areas on the surface, increased precipitations and a decrease in grain size could be observed.
View Article and Find Full Text PDFMagnesium alloys are the focus of research as resorbable materials for osteosynthesis, as they provide sufficient stability and would make surgery to remove implants unnecessary. The new degradable magnesium alloy ZEK100 was developed to improve the stability and corrosion resistance by alloying with zinc, rare earth metals and zirconium. As the implants were degraded to only a limited extent after 6 months implantation in a previous in vivo study the present study was conducted to evaluate the long-term degradation behaviour and biocompatibility in the same animal model over 9 and 12 months.
View Article and Find Full Text PDFBackground: Most studies on biodegradable magnesium implants published recently use magnesium-calcium-alloys or magnesium-aluminum-rare earth-alloys.However, since rare earths are a mixture of elements and their toxicity is unclear, a reduced content of rare earths is favorable. The present study assesses the in vivo biocompatibility of two new magnesium alloys which have a reduced content (ZEK100) or contain no rare earths at all (AX30).
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