Medical applications of superelastic nickel-titanium (Ni–Ti) alloys

The role of NiTi shape memory alloys in quality of life improvement through medical advancements: A comprehensive review

“…31,90 Other properties like its low elastic modulus close to that of human bone, great recovery strain, and high fatigue strength make it compatible for use in implants. 22,91,95 There has been considerable research into the cytotoxicity of elementary nickel and titanium, nickel especially since it is a toxic agent and allergen.…”

“…The claws are cooled to 0°C-4°C before being unfolded using needle forceps and surgically placed over the broken patella. It is then transformed into its hightemperature phase through external heating, causing the claws to contract, producing constant compressive 131 (c) micro-locking implant prosthetic system, 132 (d) active catheter, 133 (e) Simon vena cava filter, (f) stent, 95 (g) ASO prosthesis, (h) nitinol U-clip device, 134 (i) NiTi orbital floor implants, 135 (j) bone plates, 131 (k) SMA patellar concentrator, (l) compression staple, and (m) spinal spacer. 131 force on the bone, aiding proper alignment, and faster healing.…”

“…Nitinol, a category of NiTi alloys is the most widely recognized and accepted SMA for medical application. 25,90,92–95 The most desirable features of these materials are their SE, SME, as well as its high biocompatibility. Many NiTi devices have been approved for medical use by the U.S. Food and Drug Administration since 1990.…”

“…But the more commercially available Cu and Fe based SMAs, such as CuZnAl, CuAlNi, and FeMnSi, while being more economical, are limited in their usage due to their poor thermal and mechanical properties. 31,95,96 Recently research involving the application of Cu and Fe based SMAs as alternative materials have been more active but NiTi based SMAs are still the most widely used. A comparison between the three types of SMAs is given in Table 3.…”

“…31,90 Other properties like its low elastic modulus close to that of human bone, great recovery strain, and high fatigue strength make it compatible for use in implants. 22,91,95 There has been considerable research into the cytotoxicity of elementary nickel and titanium, nickel especially since it is a toxic agent and allergen. At high concentrations, nickel can cause allergic reactions and even fatal damage to living tissue, though not as much as some other materials commonly used in implants such as cobalt or vanadium.…”