title: Force-deflection comparison of superelastic nickel-titanium archwires.
abstract: This in vitro study compared the force-deflection behavior of 6 superelastic nickel-titanium orthodontic archwires (0.016 x 0.022 in) under controlled moment and temperature. To simulate leveling, maxillary canine brackets and first molar tubes were bonded in such a manner as to remove the tip and angulation from the system. The wires (n = 10) were passively self-ligated into stainless steel brackets attached to an acrylic jig to simulate the maxillary arch. A testing machine recorded deactivations of 3 distances (5, 4, and 3 mm) at 37 degrees C in the canine position. Force-deflection measurements were recorded from the deactivations only. Forces produced during deactivation, at deflections of 2.5, 2.0, and 1.5 mm, were compared by analysis of variance. Significant differences (P < 0.0001) in forces were observed among the wires at the various deflections. All wires exhibited superelastic behavior, and rankings were derived according to statistically significant differences for each deflection distance.
authors.affiliation: Department of Orthodontics, University of Texas Health Science Center at Houston, Dental Branch, 6516 M.D. Anderson Boulevard, Houston, TX 77030, USA.
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Mallory
authors.forename: Jeryl D
authors.initials: JD
authors.lastname: English
authors.forename: John M
authors.initials: JM
authors.lastname: Powers
authors.forename: William A
authors.initials: WA
authors.lastname: Brantley
authors.forename: Harry I
authors.initials: HI
authors.lastname: Bussa
mesh_terms: D000704:Analysis of Variance; D003722:Dental Alloys; D003799:Dental Stress Analysis; D004548:Elasticity; D008422:Materials Testing; D008953:Models, Anatomic; D009532:Nickel; D016382:Orthodontic Appliance Design; D016910:Orthodontic Brackets; D009969:Orthodontic Wires; D018583:Pliability; D013314:Stress, Mechanical; D013696:Temperature; D014025:Titanium
chemical_list: D003722:Dental Alloys; D009532:Nickel; D014025:Titanium