Microstructure and apatite-forming ability of the MAO-treated porous titanium

✍ Scribed by Jifeng Sun; Yong Han; Kai Cui

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 672 KB
• Volume: 202
• Category: Article
• ISSN: 0257-8972
• DOI: 10.1016/j.surfcoat.2008.03.020

✦ Synopsis

Porous titanium was treated by micro-arc oxidation (MAO) in the aqueous electrolytes containing 0.1 and 0.2 M NaOH. The microstructure (including morphology, phase component, element composition and chemical species) and in vitro apatite-forming ability of the oxidized films formed on the inner-pore walls of porous titanium were investigated. It is found that continuous thin films with pore sizes of 20-60 nm are formed in both electrolytes. The films consist of an amorphous TiO 2 outmost layer, a coexisted intermediate layer of amorphous TiO 2 and rutile, and a Ti 2 O 3 bottom layer, and tightly bond to the titanium substrate without any cracks. In vitro bioactivity assessment shows that both MAO films possess high apatite-forming abilities. It is also found that, compared with the film formed in the 0.1 M NaOH-containing electrolyte, the film formed in the 0.2 M NaOH-containing electrolyte has a higher roughness and more nanopores which help shorten apatite induction time. It is expected the MAO-formed bioactive porous titanium will not only be beneficial to bone ingrowth into the porous structure, but also be beneficial to achieve a tough chemical bonding at the bone/implant interface.