Evaluation and regulation of the corrosion resistance of macroporous titanium scaffolds with bioactive surface films for biomedical applications

Abstract

A three-layer bioactive film on porous titanium was constructed and evaluated for its corrosion resistance via electrochemical analysis.

The optimized preparation of HA/L-TiO2/D-TiO2 composite coating on porous titanium and its effect on the behavior osteoblasts

“…The fast oxidation meant that the samples were oxidized at 10 mA until the voltage climbed to 30 V, and the slow oxidation indicated that the samples were in turn oxidized at 1 mA for 30 min, 5 mA for 30 min and 10 mA until the voltage reached 30 V. Figure 2c shows the surface microstructure of the AHAO-treated samples. The D-TiO 2 layer formed between the pTi substrate and the surface L-TiO 2 layer resulted from AH treatment, as was in line with our previous report [ 30 ]. Under fast oxidation, some microcracks occurred on the surface, and the observation on the cross-section morphology showed that the L-TiO 2 layer had the tendency to fall off.…”

“…Besides, the AH or other surface-modified pTi was reported to have osteoinductivity when ectopically implanted into the body of the experimental animal for 5 months or longer time [ 14 , 38 , 39 ]. With additional AO treatment, both AHAO and AHAOEDHT samples exhibited the increased corrosion resistance in our previous study [ 30 ]. However, the AHAO sample showed weaker apatite-forming ability than the AHAOEDHT one.…”

“…Based on the previously optimized electrochemical parameters [ 29 , 30 ], the further ED process was performed on the AHAO-treated pTi samples. Figure 3 shows surface morphology and elemental compositions of the final products, i.e.…”

“…The oxidation was carried out in a constant current mode, and then the samples were placed in deionized water at 90°C for 30 min to get the AHAO samples. Finally, the pulse ED was performed on the AHAO samples at 80°C in an electrolytic cell containing electrolyte (2.5 mM Ca(NO 3 ) 2 .4H 2 O, 1.5 mM NH 4 H 2 PO 4 , 0.1 M NaCl, Ca/P = 1.67) according to our previous method [ 30 ]. The material sample, ring-shaped graphite electrode and saturated calomel electrode were used as cathode, anode and reference, respectively.…”

“…On this basis, a three-layer coating, which was composed of the inner anodized dense TiO 2 layer (D-TiO 2 ), the intermediate loose TiO 2 gel layer (L-TiO 2 ) and the outer HA layer, was prepared by an additional AO treatment. The composite coating showed the significantly improved corrosion resistance [ 30 ]. In the present study, the three-layered HA/L-TiO 2 /D-TiO 2 coating was further optimized by adjusting the processing parameters.…”