Surface characteristics and structure of anodic oxide films containing Ca and P on a titanium implant material.

An anodic oxide film that formed on titanium with a mixture of beta-glycerophosphate sodium (beta-GP) and calcium acetate was investigated. The anodic oxide had interconnected pores (ca. 1-2 microm in diameter) and intermediate roughness (0.60-1.50 microm). In addition, it contained a mixture of amorphous, anatase, and rutile oxides. With an increase in the anodizing voltage and/or concentration of calcium incorporated into the oxide, the degree of oxide crystallinity increased. However, with an increase in the concentration of beta-GP, the degree of oxide crystallinity decreased. It was concluded that the surface roughness, oxide crystallinity, and surface composition of the anodic oxide were dependent on the voltage, current density, and concentration of the electrolyte. It was also concluded that the anodized surface could be optimized for maximum osseointegration. Copyright 2002 John Wiley & Sons, Inc. J Biomed Mater Res 60: 333--338, 2002; DOI 10.1002/jbm.10105