Mimicking Bone Architecture in a Metallic Structure
The porous metallic structure has been developed to mimic the natural bone architecture, having interconnected porosity, disposing enough room to cell migration, anchoring, vascularization, nourishing and proliferation of new bone tissue. The titanium is used as porous implants due its excellent mechanical properties and biological interaction. Research evolving porous titanium has been done with purpose to achieve desirable pore size, total porosity percentage and influence of those in the increasing of bone-implant bond strength interface. Were prepared samples of titanium by powder metallurgy adding natural polymer: corn starch, rice starch, potato starch and gelatin; at proportion of 16 wt%. In aqueous solution the hydrogenated metallic powder (TiH2) and the polymer were mixed, homogenized and frozen in molds near net shape. The water was removed in kiln (38°C/12h) and the polymer by thermal treatment with air-oxidation (350 °C/1h) before sintering in high-vacuum (1300 °C/1h). Resulting from the process, the obtained pores by addition of potato and corn starchs, lead to homogenous and well distributed throughout structure. Samples obtained from addition of rice starch and gelatin formed macropores and micropores randomly distributed within the structure. The apparent porosity for all samples was near 40%. The processing technique allowed the open pore formation, in which the macropores mimics the trabecular bone structure and micropores allows the bone-implant anchorage.
Pietro Vincenzini, Luca Schenato, Nadrian C. Seeman and Friedrich C. Simmel
T. S. Goia et al., "Mimicking Bone Architecture in a Metallic Structure", Advances in Science and Technology, Vol. 84, pp. 7-12, 2013