title: Friction forces during sliding of various brackets for malaligned teeth: an in vitro study.
abstract: OBJECTIVE
  To measure the friction force generated during sliding mechanics with conventional, self-ligating (Damon 3 mx, Smart Clip, and Time 3) and low-friction (Synergy) brackets using different archwire diameters and ligating systems in the presence of apical and buccal malalignments of the canine.
  
  
  METHODS
  An experimental setup reproducing the right buccal segment of the maxillary arch was designed to measure the friction force generated at the bracket/wire and wire/ligature interfaces of different brackets. A complete factorial plan was drawn up and a three-way analysis of variance (ANOVA) was carried out to investigate whether the following factors affect the values of friction force: (i) degree of malalignment, (ii) diameter of the orthodontic wire, and (iii) bracket/ligature combination. Tukey post hoc test was also conducted to evaluate any statistically significant differences between the bracket/ligature combinations analyzed.
  
  
  RESULTS
  ANOVA showed that all the above factors affect the friction force values. The friction force released during sliding mechanics with conventional brackets is about 5-6times higher than that released with the other investigated brackets. A quasilinear increase of the frictional forces was observed for increasing amounts of apical and buccal malalignments.
  
  
  CONCLUSIONS
  The Synergy bracket with silicone ligature placed around the inner tie-wings appears to yield the best performance.
authors.affiliation: Department of Dental Sciences and Surgery, Faculty of Medicine and Surgery, University of Bari Aldo Moro, 70124 Bari, Italy.
authors.forename: Vito
authors.initials: V
authors.lastname: Crincoli
authors.forename: Letizia
authors.initials: L
authors.lastname: Perillo
authors.forename: Maria Beatrice
authors.initials: MB
authors.lastname: Di Bisceglie
authors.forename: Antonio
authors.initials: A
authors.lastname: Balsamo
authors.forename: Vitaliano
authors.initials: V
authors.lastname: Serpico
authors.forename: Francesco
authors.initials: F
authors.lastname: Chiatante
authors.forename: Carmine
authors.initials: C
authors.lastname: Pappalettere
authors.forename: Antonio
authors.initials: A
authors.lastname: Boccaccio
mesh_terms: D000704:Analysis of Variance; D003799:Dental Stress Analysis / Q000379:methods; D017276:Friction; D006801:Humans; D008310:Malocclusion / Q000517:prevention & control*; D008422:Materials Testing; D008953:Models, Anatomic; D016382:Orthodontic Appliance Design / Q000379:methods*; D016910:Orthodontic Brackets; D009969:Orthodontic Wires; D009971:Orthodontics, Corrective / Q000295:instrumentation; D013193:Stainless Steel; D013314:Stress, Mechanical
chemical_list: D013193:Stainless Steel