@article{oai:hsuh.repo.nii.ac.jp:00010012, author = {MUGURUMA, Takeshi and IIJIMA, Masahiro and YUASA, Toshihiro and OKAYAMA, Miki and MIZOGUCHI, Itaru}, issue = {1}, journal = {北海道医療大学歯学雑誌}, month = {Jun}, note = {P(論文), The aim of this study was to investigate the force delivery for a variety of types and sizes of commercially available nickel-titanium wires. The relationship of the magnitude of the force and the tooth displacement in a severe crowding case is discussed. Nine brands of nickel-titanium orthodontic wires in a variety of sizes were examined with a three-point bending test and a torsion test at 37℃. Most wires exhibited superelastic behavior for the three-point bending and torsion tests at 37℃. In the three-point bending test, the variation of the average load at 1.5mm deflection during unloading ranged from 0kgf for Copper Ni-Ti 40℃ with a 0.016×0.022 inch cross-section to 0.46kgf for ORTHO LINE with a 0.021×0.025 inch cross-section. The average torsion load at a rotation of 30°on deactivation varied from 0kgf-cm for Copper Ni-Ti 40℃ to 0.023kgf-cm for ORTHO LINE. The predicted torsional angles for the maxillary arch in the severe crowding case were smaller than expected and only three positions exceeded 20°. Considering the play between bracket slots and archwire, nickel-titanium orthodontic wires of the superelastic type may not exhibit superelastic properties for torsion in most clinical situations.}, pages = {1--7}, title = {Bending and torsional properties of commercial nickel-titanium orthodontic wires}, volume = {26}, year = {2007} }