title: Magnesium from bioresorbable implants: Distribution and impact on the nano- and mineral structure of bone.
abstract: Biocompatibility is a key issue in the development of new implant materials. In this context, a novel class of biodegrading Mg implants exhibits promising properties with regard to inflammatory response and mechanical properties. The interaction between Mg degradation products and the nanoscale structure and mineralization of bone, however, is not yet sufficiently understood. Investigations by synchrotron microbeam x-ray fluorescence (μXRF), small angle x-ray scattering (μSAXS) and x-ray diffraction (μXRD) have shown the impact of degradation speed on the sites of Mg accumulation in the bone, which are around blood vessels, lacunae and the bone marrow. Only at the highest degradation rates was Mg found at the implant-bone interface. The Mg inclusion into the bone matrix appeared to be non-permanent as the Mg-level decreased after completed implant degradation. μSAXS and μXRD showed that Mg influences the hydroxyl apatite (HAP) crystallite structure, because markedly shorter and thinner HAP crystallites were found in zones of high Mg concentration. These zones also exhibited a contraction of the HAP lattice and lower crystalline order.
authors.affiliation: Institute of Physics and Materials Science, University of Natural Resources and Life Sciences (BOKU), Vienna 1190, Austria.
authors.forename: T A
authors.initials: TA
authors.lastname: Grünewald
authors.affiliation: Institute of Physics and Materials Science, University of Natural Resources and Life Sciences (BOKU), Vienna 1190, Austria.
authors.forename: H
authors.initials: H
authors.lastname: Rennhofer
authors.affiliation: European Synchrotron Radiation Facility, Grenoble 38000, France.
authors.forename: B
authors.initials: B
authors.lastname: Hesse
authors.affiliation: European Synchrotron Radiation Facility, Grenoble 38000, France; Department of Analytical Chemistry, Ghent University, Ghent 9000, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Burghammer
authors.affiliation: Institute of Physics and Materials Science, University of Natural Resources and Life Sciences (BOKU), Vienna 1190, Austria.
authors.forename: S E
authors.initials: SE
authors.lastname: Stanzl-Tschegg
authors.affiliation: European Synchrotron Radiation Facility, Grenoble 38000, France.
authors.forename: M
authors.initials: M
authors.lastname: Cotte
authors.affiliation: Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, Zurich 8093, Switzerland.
authors.forename: J F
authors.initials: JF
authors.lastname: Löffler
authors.affiliation: Department of Orthopaedics, Medical University Graz, Graz 8010, Austria.
authors.forename: A M
authors.initials: AM
authors.lastname: Weinberg
authors.affiliation: Institute of Physics and Materials Science, University of Natural Resources and Life Sciences (BOKU), Vienna 1190, Austria. Electronic address: helga.lichtenegger@boku.ac.at.
authors.forename: H C
authors.initials: HC
authors.lastname: Lichtenegger
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D001842:Bone and Bones / Q000378:metabolism*; D002113:Calcification, Physiologic; D008274:Magnesium / Q000378:metabolism* / Q000493:pharmacokinetics; D008903:Minerals / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014961:X-Ray Diffraction
chemical_list: D001672:Biocompatible Materials; D008903:Minerals; D008274:Magnesium
keywords: Bioresorbable implant; Bone mineralization; Bone nanostructure; Implant degradation; Magnesium; X-ray microfocus techniques