Design and characterization of porous titanium scaffolds: an alternative for dental implant

The demand for dental implants is increasing, although there is a wide variety of implants currently available in the market, it is necessary to implement improvements in their design and/or the selection of materials used. The development of biomimetic and bioactive Ti scaffolds for bone regeneration is necessary. In this context, this article proposes the design, manufacture and characterization of a porous titanium implant with the aim of eliminating some of the deficiencies found in commercially available titanium implants. Stress-shielding and the lack of osseointegration or bacterial infection are still some limitations to solve. Porous samples were produced using conventional Powder Metallurgy (PM) and the space holder (SH) technique. Ammonium bicarbonate particles were used as spacers in size ranges of 100-200 μm. The porosity and surface characterization were performed by Archimedes' method and image analysis, while the mechanical behavior was analyzed by micro-mechanical testing. After that, the micromachining protocol of the implant is carried out. Substrates were chemically etched by immersion in fluorhydric acid at different times (15 s; 60 s and 125 s) to achieve a suitable surface roughness with biofunctional balance. Results showed that it is possible to obtain a desired longitudinal gradient. The optimized method described in this work suggests that it is a reasonable candidate for the development of dental implants with a good balance between reduced stress shielding and adequate mechanical strength.