In vitro evaluation of human osteoblast adhesion to a thermally oxidized γ-TiAl intermetallic alloy of composition Ti–48Al–2Cr–2Nb (at.%)

Abstract

Ti–48Al–2Cr–2Nb (at.%) (γ-TiAl), a gamma titanium aluminide alloy originally designed for aerospace applications, appears to have excellent potential as implant material. Thermal treatment of γ-TiAl renders this alloy extremely corrosion resistant in vitro, which could improve its biocompatibility. In this study, the surface oxides produced by thermal oxidation (at 500°C, and at 800°C for 1 h in air) on γ-TiAl were characterized by X-ray photoelectron spectroscopy (XPS). hFOB 1.19 cell adhesion on thermally oxidized γ-TiAl was examined in vitro by a hexosaminidase assay, scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) after 1, 7 and 14 days. Ti–6Al–4V surfaces were used for comparison. Hexosaminidase assay data and CLSM analysis of focal contacts and cytoskeleton organization showed no differences in cell attachment on autoclaved and both heat-treated γ-TiAl surfaces at the different time points. SEM images showed well organized multi-layers of differentiated cells adhered on thermally oxidized γ-TiAl surfaces at day 14. Unexpectedly, thermally oxidized Ti–6Al–4V surfaces oxidized at 800°C exhibited cytotoxic effects on hFOB 1.19 cells. Our results indicate that thermal oxidation of γ-TiAl seems to be a promising method to generate highly corrosion resistant and biocompatible surfaces for implant applications.

The effects of micro arc oxidation of gamma titanium aluminide surfaces on osteoblast adhesion and differentiation

“…After 10 days of incubation, a confluent multilayer of cells was observed on all the MAO treated surfaces, untreated γTiAl and Ti-6Al-4V disks and glass coverslips. SEM images of the cells cultured on the Ti alloy surfaces, clearly indicate that hFOB 1.19 cells exhibited normal growth on the surfaces of both MAO γTiAl and Ti-6Al-4V disks, similar to earlier reports [20,26]. The cell multilayer observed, was constituted by elongated and polygonal cells.…”

“…Recently the potential of gamma titanium aluminide (γTiAl) as a biomaterial for orthopedic applications has been extensively researched and promising indicators have been observed [17–20]. It is believed that this potential biomaterial potential for implant applications can be further enhanced by modifying the surface of γTiAl by the MAO technique.…”

Qualitative and Quantitative Analysis of Cell Proliferation Restriction Due to Metal Trace Elements Released from Oxidized Ti Alloys

“…In comparison, when oxidized at 800°C Ti-6Al-4V showed a decrease in cell attachment in comparison with gamma-TiAl on which recent studies for biocompatibility have demonstrated a good response of the metal analyzed both in vitro and in vivo 15 .…”

Wear behavior of oxidized Ti-48Al-2Cr-2Nb (at. %), Ti-6Al-4V and Cp-Ti under dry and lubricated conditions

“…%) [17][18][19] . Oxidation of this alloy (henceforth also referred to as gamma-TiAl) at 500°C and 800°C has shown contrasting behavior in terms of cytotoxicity of the oxidized surfaces [20] . A number of other studies have characterized wear behavior of both gamma titanium aluminides and their oxidized surfaces [21][22][23] albeit under rotating pin-on-disk configurations, although it is obvious that reciprocatory motion is more representative of the actual micro-motion at the bone-implant interface.…”