title: In vitro evaluation of frictional forces between archwires and ceramic brackets.
abstract: The aim of this study was to evaluate the frictional force between orthodontic brackets and archwires. The differences in magnitude of the frictional forces generated by ceramic brackets, ceramic brackets with metal reinforced slot, and stainless steel brackets in combination with stainless steel, nickel-titanium, and beta-titanium orthodontic archwires were investigated. Brackets and wire were tested with tip angulations of 0 degrees and 10 degrees. Friction testing was done with the Emic DL 10000 testing machine (São José do Rio Preto, PR, Brazil), and the wires were pulled from the slot brackets with a speed of 0.5 cm/min for 2 minutes. The ligation force between the bracket and the wire was 200 g. According to the data obtained, the brackets had frictional force values that were statistically significant in this progressive order: stainless steel bracket, ceramic bracket with a metal reinforced slot, and traditional ceramic bracket with a ceramic slot. The beta-titanium wire showed the highest statistically significant frictional force value, followed by the nickel-titanium and the stainless steel archwires, in decreasing order. The frictional force values were directly proportional to the angulation increase between the bracket and the wire.
authors.affiliation: Department of Orthodontics, Universidade Federal Fluminense, Niteroi, RJ, Brazil. cnishio@unisys.com.br
authors.forename: Clarice
authors.initials: C
authors.lastname: Nishio
authors.forename: Andréa Fonseca Jardim
authors.initials: AF
authors.lastname: da Motta
authors.forename: Carlos Nelson
authors.initials: CN
authors.lastname: Elias
authors.forename: José Nelson
authors.initials: JN
authors.lastname: Mucha
mesh_terms: D002516:Ceramics; D003722:Dental Alloys; D003799:Dental Stress Analysis; D017276:Friction; D008422:Materials Testing; D009532:Nickel; D016382:Orthodontic Appliance Design; D016910:Orthodontic Brackets; D009969:Orthodontic Wires; D013193:Stainless Steel; D014025:Titanium
chemical_list: D003722:Dental Alloys; C023988:beta titanium; C040654:titanium nickelide; D013193:Stainless Steel; D009532:Nickel; D014025:Titanium