title: Oxidized nickel-titanium foams for bone reconstructions: chemical and mechanical characterization.
abstract: This work examines NiTi foams that have been treated using a new oxidation treatment for obtaining Ni-free surfaces that could allow the ingrowth of living tissue, thereby increasing the mechanical anchorage of implants. A significant increase in the real surface area of these materials can decrease corrosion resistance and favour the release of Ni. This chemical degradation can induce allergic reactions or toxicity in the surrounding tissues. This study determines the porosity, surface characteristics, phase transformation, mechanical properties, corrosion behaviour and Ni release into the simulated body fluid medium of foams treated by a new surface oxidation treatment that produces Ni-free surfaces. These foams have pores in an appropriate range of sizes and interconnectivity, and thus their morphology is similar to that of bone. Their mechanical properties are biomechanically compatible with bone. The titanium oxide on the surface significantly improves corrosion resistance and decreases nickel ion release, while barely affecting transformation temperatures.
authors.affiliation: CREB, Departamento de Ciencia de Materiales e Ingeniería Metalúrgica, ETSEIB, Universidad Politécnica de Cataluña, Diagonal 647, 08028 Barcelona, Spain,
authors.forename: Maite
authors.initials: M
authors.lastname: Barrabés
authors.forename: Alexandra
authors.initials: A
authors.lastname: Michiardi
authors.forename: Conrado
authors.initials: C
authors.lastname: Aparicio
authors.forename: Pablo
authors.initials: P
authors.lastname: Sevilla
authors.forename: Josep A
authors.initials: JA
authors.lastname: Planell
authors.forename: Francisco Javier
authors.initials: FJ
authors.lastname: Gil
mesh_terms: D015502:Absorptiometry, Photon; D001696:Biomechanical Phenomena; D001826:Body Fluids / Q000737:chemistry / Q000502:physiology; D001861:Bone Regeneration; D019245:Compressive Strength; D003343:Corrosion; D016319:Corrosion Casting; D006801:Humans; D008422:Materials Testing; D009532:Nickel / Q000737:chemistry* / Q000378:metabolism / Q000493:pharmacokinetics / Q000627:therapeutic use*; D010084:Oxidation-Reduction; D044367:Phase Transition; D016062:Porosity; D013499:Surface Properties; D013696:Temperature; D054457:Tissue Scaffolds / Q000737:chemistry; D014025:Titanium / Q000737:chemistry* / Q000378:metabolism / Q000627:therapeutic use*
chemical_list: C040654:titanium nickelide; D009532:Nickel; D014025:Titanium