Untitled

Abstract

Biological properties of titanium implant depend on its surface oxide film. In the present study, the surface oxide films on titanium were characterized and the relationship between the characterization and bioactivity of titanium was studied. The surface oxide films on titanium were obtained by heat-treatment in different oxidation atmospheres, such as air, oxygen and water vapor. The bioactivity of heat-treated titanium plates was investigated by immersion test in a supersaturated calcium phosphate solution. The surface roughness, energy morphology, chemical composition and crystal structure were used to characterize the titanium surfaces. The characterization was performed using profilometer, scanning electronic microscopy, ssesile drop method, X-ray photoelectron spectroscopy, common Bragg X-ray diffraction and sample tilting X-ray diffraction. Percentage of surface hydroxyl groups was determined by X-ray photoelectron spectroscopy analysis for titanium plates and density of surface hydroxyl groups was measured by chemical method for titanium powders. The results indicated that heat-treatment uniformly roughened the titanium surface and increased surface energy. After heat-treatment the surface titanium oxide was predominantly rutile TiO(2), and crystal planes in the rutile films preferentially orientated in (1 1 0) plane with the highest density of titanium ions. Heat-treatment increased the amount of surface hydroxyl groups on titanium. The different oxidation atmospheres resulted in different percentages of oxygen species in TiO(2), in physisorbed water and acidic hydroxyl groups, and in basic hydroxyl groups on the titanium surfaces. The immersion test in the supersaturated calcium phosphate solution showed that apatite spontaneously formed on to the rutile films. This revealed that rutile could be bioactivated. The analyses for the apatite coatings confirmed that the surface characterization of titanium has strong effect on bioactivity of titanium. The bioactivity of the rutile films on titanium was related not only to their surface basic hydroxyl groups, but also to acidic hydroxyl groups, and surface energy. Heat-treatment endowed titanium with bioactivity by increasing the amount of surface hydroxyl groups on titanium and its surface energy.

Effects of anodizing conditions on bond strength of anodically oxidized film to titanium substrate

“…However, titanium is a bioinert material that neither chemically connects to bone nor actively induces bone growth. Therefore, various surface modifications of titanium implants have been carried out to improve its bioactivity [4][5][6][7].…”

Influence of CO2 exposure on pH value, electrochemical properties, and the formation of calcium-phosphate on Ti–6Al–4V under adjusted in vitro conditions in DMEM

“…The revealed peaks at 529 or 530 eV can be attributed to oxygen of the surface oxide layer of TiO 2 (Ti-O) [32,33]. Surface acidic and basic hydroxyl groups (531 and 532 eV) are bound to two surface titanium atoms, whereas the basic OH (532 or 534 eV) is bound to one surface titanium atom [34][35][36]. In all high resolution scans, the major contribution to the O1s peak resulted from the formation of Ti-O.…”

A novel microwave recipe for an antibiofilm titanium surface

“…It is reported that bacterial cells have the highest affinity for rutile. The reasons speculated include the reported [42] increase in the bioactivity of the rutile surface due to heat treatment. Feng et al report that rutile TiO 2 forms at higher temperatures and that during heat treatment, oxygen and water react with the titanium surface, increasing the amount of hydroxyl groups on the surface and also thickening of the oxide film.…”