Porous NiTi for bone implants: a review.
NiTi foams are unique among biocompatible porous metals because of their high recovery strain (due to the shape-memory or superelastic effects) and their low stiffness facilitating integration with bone structures. To optimize NiTi foams for bone implant applications, two key areas are under active study: synthesis of foams with optimal architectures, microstructure and mechanical properties; and tailoring of biological interactions through modifications of pore surfaces. This article reviews recent research on NiTi foams for bone replacement, focusing on three specific topics: (i) surface modifications designed to create bio-inert porous NiTi surfaces with low Ni release and corrosion, as well as bioactive surfaces to enhance and accelerate biological activity; (ii) in vitro and in vivo biocompatibility studies to confirm the long-term safety of porous NiTi implants; and (iii) biological evaluations for specific applications, such as in intervertebral fusion devices and bone tissue scaffolds. Possible future directions for bio-performance and processing studies are discussed that could lead to optimized porous NiTi implants.
Bansiddhi
A
A
Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA. ampikaa@gmail.com
Sargeant
T D
TD
Stupp
S I
SI
Dunand
D C
DC
D000497:Alloys / Q000737:chemistry*; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D018786:Bone Substitutes / Q000737:chemistry*; D016062:Porosity; D019736:Prostheses and Implants; D013499:Surface Properties
D000497:Alloys; D001672:Biocompatible Materials; D018786:Bone Substitutes; C013616:nitinol