title: In vivo assessments of bioabsorbable AZ91 magnesium implants coated with nanostructured fluoridated hydroxyapatite by MAO/EPD technique for biomedical applications.
abstract: Although magnesium (Mg) is a unique biodegradable metal which possesses mechanical property similar to that of the natural bone and can be an attractive material to be used as orthopedic implants, its quick corrosion rate restricts its actual clinical applications. To control its rapid degradation, we have modified the surface of magnesium implant using fluoridated hydroxyapatite (FHA: Ca10(PO4)6OH2-xFx) through the combined micro-arc oxidation (MAO) and electrophoretic deposition (EPD) techniques, which was presented in our previous paper. In this article, the biocompatibility examinations were conducted on the coated AZ91 magnesium alloy by implanting it into the greater trochanter area of rabbits. The results of the in vivo animal test revealed a significant enhancement in the biocompatibility of FHA/MAO coated implant compared to the uncoated one. By applying the FHA/MAO coating on the AZ91 implant, the amount of weight loss and magnesium ion release in blood plasma decreased. According to the histological results, the formation of the new bone increased and the inflammation decreased around the implant. In addition, the implantation of the uncoated AZ91 alloy accompanied by the release of hydrogen gas around the implant; this release was suppressed by applying the coated implant. Our study exemplifies that the surface coating of magnesium implant using a bioactive ceramic such as fluoridated hydroxyapatite may improve the biocompatibility of the implant to make it suitable as a commercialized biomedical product.
authors.affiliation: Biomaterials Research Group, Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran; Dental Materials Research Center, Isfahan University of Medical Sciences, Isfahan, Iran; Torabinejad Dental Research Center, School of Dentistry, Isfahan University of Medical Sciences, Isfahan 81746-73461, Iran; School of Materials Science and Engineering, Helmerich Advanced Technology Research Center, Oklahoma State University, Tulsa, OK 74106, USA. Electronic address: mrazavi2659@gmail.com.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Razavi
authors.affiliation: Biomaterials Research Group, Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran; Dental Materials Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Mohammadhossein
authors.initials: M
authors.lastname: Fathi
authors.affiliation: Torabinejad Dental Research Center, School of Dentistry, Isfahan University of Medical Sciences, Isfahan 81746-73461, Iran.
authors.forename: Omid
authors.initials: O
authors.lastname: Savabi
authors.affiliation: School of Electrical and Computer Engineering, Helmerich Advanced Technology Research Center, Oklahoma State University, Tulsa, OK 74106, USA.
authors.forename: Daryoosh
authors.initials: D
authors.lastname: Vashaee
authors.affiliation: School of Materials Science and Engineering, Helmerich Advanced Technology Research Center, Oklahoma State University, Tulsa, OK 74106, USA; Department of Developmental Sciences, Marquette University School of Dentistry, Milwaukee, WI 53201, USA; Biomaterials and Advanced Drug Delivery Laboratory, Stanford University, Stanford, CA 94305, USA. Electronic address: lobat.tayebi@okstate.edu.
authors.forename: Lobat
authors.initials: L
authors.lastname: Tayebi
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D002470:Cell Survival; D020099:Coated Materials, Biocompatible / Q000378:metabolism; D003343:Corrosion; D004586:Electrophoresis / Q000379:methods; D006882:Hydroxyapatites / Q000737:chemistry*; D008274:Magnesium; D008422:Materials Testing / Q000379:methods; D016876:Metal Ceramic Alloys / Q000737:chemistry; D046529:Microscopy, Electron, Transmission; D049329:Nanostructures / Q000737:chemistry*; D011817:Rabbits; D014961:X-Ray Diffraction
chemical_list: D020099:Coated Materials, Biocompatible; D006882:Hydroxyapatites; D016876:Metal Ceramic Alloys; C028869:fluor-hydroxylapatite; D008274:Magnesium
keywords: Bioabsorbable magnesium alloy; Coating; Fluoridated hydroxyapatite; Surface modification; in vivo