Comparison of low-pressure oxygen plasma and chemical treatments for surface modifications of Ti6Al4V

Different treatments were conducted over Ti6Al4V samples in order to produce a surface modification to increase cell attachment and proliferation. The surface treatments evaluated in this study were as follows: etching with sulfuric acid/hydrochloric acid, oxidizing with hydrogen peroxide and low-pressure oxygen plasma treatment. In contrast to other works found in the literature, this research conducts a comparison between different chemical and physical treatments in terms of different assays for surface characterization: X-ray diffraction, scanning electron microscope(SEM), energy-dispersive X-ray spectroscopy, water contact angle, release of vanadiumions and cell viability tests(MTT) of human osteoblasts(hFOB 1.19). Cell morphology over the different substrates was also studied by SEM observation. It was found that plasma and peroxide treatments increase the O/Ti ratio at the titanium surface and provide an increase in cell affinity. On the other hand, acid etching provides a superhydrophilic surface which is not able to improve the cell attachment of human osteoblasts.