title: The bone tissue compatibility of a new Ti-Nb-Sn alloy with a low Young's modulus.
abstract: A Ti-Nb-Sn alloy was developed as a new β-type titanium alloy which had a low Young's modulus and high strength. The Young's modulus of the Ti-Nb-Sn alloy was reduced to about 45 GPa by cold rolling, much closer to human cortical bone (10-30 GPa) than that of Ti-6Al-4V alloy (110 GPa) and other β-type titanium alloys developed for biomedical applications. The tensile strength of the Ti-Nb-Sn alloy was increased to a level greater than that of Ti-6Al-4V alloy by heat treatment after severe cold rolling. In this study the cytotoxicity of Ti-25Nb-11Sn alloy was evaluated in direct contact cell culture tests using metal disks and the bone tissue compatibility - examined using metal rods inserted into the medullary canal of rabbit femurs. The remarkable findings were that: (1) there were no significant differences in the relative growth ratio and relative absorbance ratio between cells grown with the Ti-Nb-Sn alloy, Ti-6Al-4V alloy and CP-Ti in direct contact cell culture tests; (2) there were no significant differences in the load at failure between the Ti-Nb-Sn alloy and Ti-6Al-4V alloy in pull-out metal rods tests; (3) there were no significant differences in new bone formation around metal rods between the Ti-Nb-Sn alloy and Ti-6Al-4V alloy in histological evaluations. The new Ti-Nb-Sn alloy with an elasticity closer to that of human bone is thus considered to be bioinert while also having a high degree of bone compatibility similar to that of Ti-6Al-4V alloy.
authors.affiliation: Department of Orthopedic Surgery, Tohoku University Graduate School of Medicine, Seiryo-machi, Aoba-ku, Sendai, Miyagi, Japan.
authors.forename: Keiki
authors.initials: K
authors.lastname: Miura
authors.forename: Norikazu
authors.initials: N
authors.lastname: Yamada
authors.forename: Shuji
authors.initials: S
authors.lastname: Hanada
authors.forename: Taek-Kyun
authors.initials: TK
authors.lastname: Jung
authors.forename: Eiji
authors.initials: E
authors.lastname: Itoi
mesh_terms: D000497:Alloys / Q000494:pharmacology*; D000818:Animals; D001672:Biocompatible Materials / Q000494:pharmacology*; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000502:physiology; D016923:Cell Death / Q000187:drug effects; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D055119:Elastic Modulus / Q000187:drug effects*; D005269:Femur / Q000000981:diagnostic imaging / Q000187:drug effects / Q000502:physiology; D006801:Humans; D008422:Materials Testing / Q000379:methods*; D051379:Mice; D009556:Niobium / Q000494:pharmacology; D011817:Rabbits; D011859:Radiography; D014001:Tin / Q000494:pharmacology; D014025:Titanium / Q000494:pharmacology; D016474:Weight-Bearing / Q000502:physiology
chemical_list: D000497:Alloys; D001672:Biocompatible Materials; D009556:Niobium; D014001:Tin; D014025:Titanium