Novel Chemical Treatment of Porous Titanium Structures for Nanotextured Surface and Bioactive Behavior

Macroporous titanium structures are of interest in bone reconstruction because of their reduced modulus of elasticity (compared to bulk titanium), possibility of being colonized by cells, and biocompatibility. However, they are not bioactive and are not able to actively facilitate bone ingrowth or reduce bacterial adhesion. In the present research, work porous titanium scaffolds with different features (porosity 30–60 vol% and pore size 100–200 or 355–500 μm) are obtained by the space holder technique. Samples are characterized using optical microscopy, computed tomography, scanning electron microscopy (SEM), and X-ray diffraction. Moreover, the theoretical elastic modulus and yield strength are calculated. A patented chemical treatment, able to produce a bioactive nanotextured oxide layer, has been optimized and successfully applied, for the first time, to structures with 50 vol% porosity and 100–200 μm pore size (as the most promising for bone substitution due to the biomechanical and biofunctional balance). Bare and modified samples are characterized using field emission SEM, zeta potential measurements, and in vitro bioactivity tests (soaking in simulated body solution) to evaluate the effectiveness of the surface chemical treatment.