Chemical Composition and Morphology of Titanium Surface Oxides

Titanium has emerged as one of the most tissue-compatible metallic materials. The high degree of biocompatibility is intimately connected with the oxide that forms on the metal surface. In the present work a broad characterization has been made of titanium samples pretreated both by presently used clinical procedures (mechanical machining, ultrasonic cleaning and autoclaving) and by alternative preparation procedures such as electropolishing and anodic oxidation. The former samples are found to have a surface oxide of TiO 2 which is 30–50 A thick, with some trace element contamination and a relatively large carbon content (30–50 % of a monoatomic layer). The anodically oxidized samples also consist of TiO 2 with an oxide thickness range of 50–2000 A, but the morphology and crystallinity of the anodic oxides are found to depend on thickness and preparation conditions. The main methods of investigation used in the present study were ESCA, SIMS and transmission electron microscopy.