title: Cytocompatibility of a free machining titanium alloy containing lanthanum.
abstract: Titanium alloys like Ti6Al4V are widely used in medical engineering. However, the mechanical and chemical properties of titanium alloys lead to poor machinability, resulting in high production costs of medical products. To improve the machinability of Ti6Al4V, 0.9% of the rare earth element lanthanum (La) was added. The microstructure, the mechanical, and the corrosion properties were determined. Lanthanum containing alloys exhibited discrete particles of cubic lanthanum. The mechanical properties and corrosion resistance were slightly decreased but are still sufficient for many applications in the field of medical engineering. In vitro experiments with mouse macrophages (RAW 264.7) and human bone-derived cells (MG-63, HBDC) were performed and revealed that macrophages showed a dose response below and above a LaCl3 concentration of 200 microM, while MG-63 and HBDC tolerated three times higher concentrations without reduction of viability. The viability of cells cultured on disks of the materials showed no differences between the reference and the lanthanum containing alloy. We therefore propose that lanthanum containing alloy appears to be a good alternative for biomedical applications, where machining of parts is necessary.
authors.affiliation: Department for Macromolecular Structure Research, GKSS Forschungszentrum Geesthacht GmbH, Institute of Materials Research, Max-Planck-Str. 1, D-21502 Geesthacht, Germany. frank.feyerabend@gkss.de
authors.forename: Frank
authors.initials: F
authors.lastname: Feyerabend
authors.forename: Carsten
authors.initials: C
authors.lastname: Siemers
authors.forename: Regine
authors.initials: R
authors.lastname: Willumeit
authors.forename: Joachim
authors.initials: J
authors.lastname: Rösler
mesh_terms: D000497:Alloys / Q000737:chemistry*; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D001842:Bone and Bones / Q000166:cytology / Q000187:drug effects; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007811:Lanthanum / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects; D008422:Materials Testing; D051379:Mice; D014025:Titanium
chemical_list: D000497:Alloys; D001672:Biocompatible Materials; C028521:lanthanum chloride; D007811:Lanthanum; D014025:Titanium