Comparison of the kinetic frictional force between conventional plastic brackets with thermoplastic low-friction module ligation and self-ligating brackets.
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.
Yanase
Yumi
Y
Department of Orthodontics, Faculty of Dentistry, Kyushu University, Fukuoka, Japan.
Ioi
Hideki
H
Uehara
Michiya
M
Hara
Atsushi
A
Nakata
Shunsuke
S
Nakasima
Akihiko
A
Counts
Amy L
AL
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
D003722:Dental Alloys; D003764:Dental Materials; D010969:Plastics; C040654:titanium nickelide; D013193:Stainless Steel; D009532:Nickel; D014025:Titanium