title: In vitro corrosion of ZEK100 plates in Hank's Balanced Salt Solution.
abstract: BACKGROUND
  In recent years magnesium alloys have been intensively investigated as potential resorbable materials with appropriate mechanical and corrosion properties. Particularly in orthopedic research magnesium is interesting because of its mechanical properties close to those of natural bone, the prevention of both stress shielding and removal of the implant after surgery.
  
  
  METHODS
  ZEK100 plates were examined in this in vitro study with Hank's Balanced Salt Solution under physiological conditions with a constant laminar flow rate. After 14, 28 and 42 days of immersion the ZEK100 plates were mechanically tested via four point bending test. The surfaces of the immersed specimens were characterized by SEM, EDX and XRD.
  
  
  RESULTS
  The four point bending test displayed an increased bending strength after 6 weeks immersion compared to the 2 week group and 4 week group. The characterization of the surface revealed the presence of high amounts of O, P and Ca on the surface and small Mg content. This indicates the precipitation of calcium phosphates with low solubility on the surface of the ZEK100 plates.
  
  
  CONCLUSIONS
  The results of the present in vitro study indicate that ZEK100 is a potential candidate for degradable orthopedic implants. Further investigations are needed to examine the degradation behavior.
authors.affiliation: Department of Orthopedic Surgery, Hannover Medical School, Anna-von-Borries-Str,1-7, 30625 Hannover, Germany. Hazibullah.Waizy@ddh-gruppe.de
authors.forename: Hazibullah
authors.initials: H
authors.lastname: Waizy
authors.forename: Andreas
authors.initials: A
authors.lastname: Weizbauer
authors.forename: Christian
authors.initials: C
authors.lastname: Modrejewski
authors.forename: Frank
authors.initials: F
authors.lastname: Witte
authors.forename: Henning
authors.initials: H
authors.lastname: Windhagen
authors.forename: Arne
authors.initials: A
authors.lastname: Lucas
authors.forename: Marc
authors.initials: M
authors.lastname: Kieke
authors.forename: Berend
authors.initials: B
authors.lastname: Denkena
authors.forename: Peter
authors.initials: P
authors.lastname: Behrens
authors.forename: Andrea
authors.initials: A
authors.lastname: Meyer-Lindenberg
authors.forename: Friedrich-Wilhelm
authors.initials: FW
authors.lastname: Bach
authors.forename: Fritz
authors.initials: F
authors.lastname: Thorey
mesh_terms: D000497:Alloys / Q000737:chemistry*; D001639:Bicarbonates / Q000737:chemistry*; D001672:Biocompatible Materials / Q000737:chemistry*; D003343:Corrosion; D057446:Hydrodynamics; D007101:Immersion; D007552:Isotonic Solutions / Q000737:chemistry*; D008274:Magnesium / Q000737:chemistry*; D055595:Mechanical Phenomena; D013499:Surface Properties
chemical_list: D000497:Alloys; D001639:Bicarbonates; D001672:Biocompatible Materials; C072670:Hanks Balanced Salt Solution; D007552:Isotonic Solutions; D008274:Magnesium