Surface properties and bio-acceptability of Ti2O3 surfaces

TiO2 has been identified as a major and probably most desired surface for high bio-acceptability. South African manufactured implant surfaces revealed that Ti2O3 is the predominant surface layer. Chemical surface characteristics after evaluation of Ti2O3 surfaces using X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) showed surfaces to be relatively free from contamination by unwanted chemical elements. Surface layers of different Ti-core metals consisted mainly of Ti. O and C. XPS analysis of surface oxide layers on all Ti-surfaces showed mainly Ti2O3 and TiO in smaller quantities. When evaluating in vitro bio-acceptability, percentage attachment efficiency and proliferation (%-AEP) of human fetal fibroblasts (HFF) and human gingival fibroblast (HGF) on Ti-surfaces showed that the Ti2O3-surface oxide furnished a highly bio-acceptable surface. Evaluation of attached HGF on Ti-surfaces using scanning electron microscopy (SEM) showed fibroblasts attached and spread on Ti-surfaces by formation of numerous filopodia. Metal leaching as determined using inductively coupled plasma emission spectroscopy (ICP) were practically absent for all Ti2O3-surfaces. Absence of toxic metals (V, Pd) on surfaces prepared from Ti-6Al-4V-alloy and Ti with Pd impurity, and practical absence of metal leaching, indicated that these metals did not compete for oxidation of the surface and indicated a possible masking effect of the metal surface by the Ti2O3-surface oxide layer. Implants with Ti2O3-surfaces are widely used in South Africa and have proved to be very successful. (C) 1998 Elsevier Science S.A. All rights reserved.