Superficial treatment by anodization in order to obtain titanium oxide nanotubes applicable in implantology

Influence of simulated body fluid (normal and inflammatory) on corrosion resistance of anodized titanium

“…Nevertheless, even with the low current density observed during anodization and the transients behaving in a similarly way in different anodizing electrolytes, the formation of nanotubes in the titanium samples anodized with 1 mol L -1 aquous solution of H3PO4 added of 0.15% (w/v) HF, was expected due to the presence of HF in the electrolyte, causing oxide transition of the barrier type to the porous type. The formation of nanotubes was already observed by Kunst (Kunst et al, 2020), but the anodizing transients showed behavior of barrier oxide formation despite forming nanotubes. Unfortunately, according to the literature (Kowalski, 2013), the formation of some nanostructures such as TiO2 nanotubes, are more complex…”

“…On the other hand, on the samples anodized in 1 mol L -1 H3PO4 + 0.15% HF for 30 minutes and shown in Figure 2 e and f, the tubes described by Kunst (Kunst et al, 2020) are not observed. However, is possible to observe small clusters, such as nodules or agglomerates on the metal surface.…”

“…The sample was connected as anode and platinum as cathode. The electrolytes used for anodization were 1 mol L -1 aquous solution of H3PO4 and 1 mol L -1 aquous solution of H3PO4 added of 0.15% (w/v) HF (Kunst et al, 2020), to obtain barrier and porous oxides respectivelly.…”

“…In the barrier type titanium oxide, under specific conditions, the migration rate of fluorides throught the oxide towards the metal is twice as high as that of oxygen ions. The layer plenty of fluoride ions and deficient in oxygen is often found at the base of the oxide (metal/oxide interface), which is soluble in water, causing preferential paths for the formation of nanotubular TiO2 (Kunst et al, 2020).…”

“…Literature shows that titanium plates anodized in H3PO4/HF electrolytes present nanotubes with an average diameter of around 70 nm. This diameter is considered adequate for osseointegration, whose average pore spacing must place between 15 nm and 30 nm and for a surface containing tubes, this distance should not exceed 70 nm (Park et al, 2007;Kunst et al, 2020).…”