title: Comparison of the kinetic frictional force between conventional plastic brackets with thermoplastic low-friction module ligation and self-ligating brackets.
abstract: OBJECTIVE
  To compare the kinetic frictional force of a conventional plastic preadjusted bracket with thermoplastic low-friction module ligation and a self-ligating bracket.
  
  
  METHODS
  The testing model consisted of four 0.022-inch conventional plastic preadjusted brackets; four 0.022-inch self-ligating brackets for the first premolar, canine, and lateral and central incisors; and a 0.014-inch superelastic nickel-titanium and a 0.019 × 0.025-inch stainless steel wire. The brackets were either aligned for both wires or out of line by 0.5, 1.0, 1.5, and 2.0 mm for only the 0.014-inch superelastic wire. The wires were pulled for 3.0 mm at a speed of 0.1 mm per second. Unpaired t tests were used to compare the mean differences of the measurements between the two bracket systems with both wires.
  
  
  RESULTS
  No significant difference in the kinetic frictional force between the two bracket systems and the two wires were found for the 0.014-inch superelastic wire at 0-mm deflection.
  
  
  CONCLUSIONS
  Both bracket systems demonstrate low friction, which is beneficial for effective orthodontic tooth movement with light forces.
authors.affiliation: Department of Orthodontics, Faculty of Dentistry, Kyushu University, Fukuoka, Japan.
authors.forename: Yumi
authors.initials: Y
authors.lastname: Yanase
authors.forename: Hideki
authors.initials: H
authors.lastname: Ioi
authors.forename: Michiya
authors.initials: M
authors.lastname: Uehara
authors.forename: Atsushi
authors.initials: A
authors.lastname: Hara
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Nakata
authors.forename: Akihiko
authors.initials: A
authors.lastname: Nakasima
authors.forename: Amy L
authors.initials: AL
authors.lastname: Counts
mesh_terms: D001641:Bicuspid / Q000473:pathology; D003481:Cuspid / Q000473:pathology; D003722:Dental Alloys / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry*; D004548:Elasticity; D017276:Friction; D006801:Humans; D007180:Incisor / Q000473:pathology; D009532:Nickel / Q000737:chemistry; D016382:Orthodontic Appliance Design; D016910:Orthodontic Brackets; D009969:Orthodontic Wires; D010969:Plastics / Q000737:chemistry*; D013193:Stainless Steel / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry; D014087:Tooth Movement Techniques / Q000295:instrumentation
chemical_list: D003722:Dental Alloys; D003764:Dental Materials; D010969:Plastics; C040654:titanium nickelide; D013193:Stainless Steel; D009532:Nickel; D014025:Titanium