title: Effects of topography and composition of titanium surface oxides on osteoblast responses.
abstract: To investigate the roles of composition and characteristics of titanium surface oxides in cellular behaviour of osteoblasts, the surface oxides of titanium were modified in composition and topography by anodic oxidation in two kinds of electrolytes, (a) 0.2 M H(3)PO(4), and (b) 0.03 M calcium glycerophosphate (Ca-GP) and 0.15 M calcium acetate (CA), respectively. Phosphorus (P: ca.10at%) or both calcium (Ca: 1-6at%) and phosphorus (P: 3-6at%) were incorporated into the anodized surfaces in the form of phosphate and calcium phosphate. Surface roughness was slightly decreased or enhanced (R(a) in the range of 0.1-0.5 microm) on the anodized surfaces. The geometry of the micro-pores in the anodized surfaces varied with diameters up to 0.5 microm in 0.2 M H(3)PO(4) and to 2 microm in 0.03 M Ca-GP and 0.15 M CA, depending on voltages and electrolyte. Contact angles of all the anodic oxides were in the range of 60-90 degrees. Cell culture experiments demonstrated absence of cytotoxicity and an increase of osteoblast adhesion and proliferation by the anodic oxides. Cells on the surfaces with micro-pores showed an irregular and polygonal growth and more lamellipodia, while osteoblasts on the titanium surface used as a control or on anodic oxides formed at low voltages showed many thick stress fibres and intense focal contacts. Alkaline phosphatase (ALP) activity of the cells did not show any correlation with surface characteristics of anodic oxides.
authors.affiliation: Department of Prosthodontics and Medical Materials, Section of Medical Materials and Technology, University of Tuebingen, Osianderstr. 2-8, Tuebingen D-72076, Germany. xialong.zhu@med.uni-teubingen.de
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Zhu
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.forename: Lutz
authors.initials: L
authors.lastname: Scheideler
authors.forename: Rudolf
authors.initials: R
authors.lastname: Reichl
authors.forename: Juergen
authors.initials: J
authors.lastname: Geis-Gerstorfer
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D002448:Cell Adhesion / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D002460:Cell Line; D002465:Cell Movement / Q000502:physiology*; D002470:Cell Survival / Q000502:physiology; D004595:Electroplating / Q000379:methods; D006801:Humans; D008422:Materials Testing; D008968:Molecular Conformation; D010006:Osteoblasts / Q000166:cytology* / Q000502:physiology*; D010084:Oxidation-Reduction; D016062:Porosity; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; C009495:titanium dioxide; D014025:Titanium