Preparation of bioactive titania films on titanium metal via anodic oxidation.
OBJECTIVE
To research the crystal structure and surface morphology of anodic films on titanium metal in different electrolytes under various electrochemical conditions and investigate the effect of the crystal structure of the oxide films on apatite-forming ability in simulated body fluid (SBF).


METHODS
Titanium oxide films were prepared using an anodic oxidation method on the surface of titanium metal in four different electrolytes: sulfuric acid, acetic acid, phosphoric acid and sodium sulfate solutions with different voltages for 1 min at room temperature.


RESULTS
Anodic films that consisted of rutile and/or anatase phases with porous structures were formed on titanium metal after anodizing in H(2)SO(4) and Na(2)SO(4) electrolytes, while amorphous titania films were produced after anodizing in CH(3)COOH and H(3)PO(4) electrolytes. Titanium metal with the anatase and/or rutile crystal structure films showed excellent apatite-forming ability and produced a compact apatite layer covering all the surface of titanium after soaking in SBF for 7d, but titanium metal with amorphous titania layers was not able to induce apatite formation.


CONCLUSIONS
The resultant apatite layer formed on titanium metal in SBF could enhance the bonding strength between living tissue and the implant. Anodic oxidation is believed to be an effective method for preparing bioactive titanium metal as an artificial bone substitute even under load-bearing conditions.
Cui
X
X
Institute of Metal Research, Chinese Academy of Sciences, Shenyang, China.
Kim
H-M
HM
Kawashita
M
M
Wang
L
L
Xiong
T
T
Kokubo
T
T
Nakamura
T
T
D019342:Acetic Acid / Q000737:chemistry; D001031:Apatites / Q000737:chemistry; D001672:Biocompatible Materials / Q000737:chemistry*; D003461:Crystallography; D003764:Dental Materials / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000379:methods; D004573:Electrolytes / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010084:Oxidation-Reduction; D010756:Phosphoric Acids / Q000737:chemistry; D010949:Plasma / Q000737:chemistry; D016062:Porosity; D013431:Sulfates / Q000737:chemistry; D013464:Sulfuric Acids / Q000737:chemistry; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014025:Titanium / Q000737:chemistry*; D014961:X-Ray Diffraction
D001031:Apatites; D001672:Biocompatible Materials; D003764:Dental Materials; D004573:Electrolytes; D010756:Phosphoric Acids; D013431:Sulfates; D013464:Sulfuric Acids; C012036:sodium sulfate; C009495:titanium dioxide; D014025:Titanium; C030242:phosphoric acid; C033158:sulfuric acid; D019342:Acetic Acid