title: Opening and closure forces of sliding mechanisms of different self-ligating brackets.
abstract: Self-ligating brackets engage the wire by means of a slide mechanism. Forces that have to be applied to open and close the sliding mechanism of brackets are still unknown.
  
  
  OBJECTIVE
  The aim of this study was to measure and compare the opening and closure forces of different self-ligating brackets.
  
  
  METHODS
  Three different stainless steel self-ligating brackets (Carriere LX, Ortho Organizers; F1000, Leone; Damon Q, Ormco) were tested. For each different bracket, 20 maxillary right central incisors and 20 mandibular right central incisors were used. Opening and closure forces were measured using an Instron Universal Testing Machine. Statistical analysis was performed and ANOVA and Tukey tests were carried out.
  
  
  RESULTS
  Opening forces were registered between 1.1 N and 5.6 N, whereas closure forces were recorded between 1.57 N and 4.87 N. Significant differences were detected among the different brackets and between the two prescriptions tested.
  
  
  CONCLUSIONS
  The knowledge of different opening and closure forces of self-ligating brackets can help the orthodontist in the clinical management of these devices.
authors.affiliation: Unit of Orthodontics, Department of Clinical, Surgical, Diagnostic and Pediatric Sciences, School of Dentistry, University of Pavia, Pavia, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Gandini
authors.forename: Linda
authors.initials: L
authors.lastname: Orsi
authors.forename: Maria Francesca
authors.initials: MF
authors.lastname: Sfondrini
authors.forename: Andrea
authors.initials: A
authors.lastname: Scribante
mesh_terms: D000704:Analysis of Variance; D001696:Biomechanical Phenomena; D008422:Materials Testing; D016382:Orthodontic Appliance Design; D016910:Orthodontic Brackets; D012016:Reference Values; D013193:Stainless Steel; D018709:Statistics, Nonparametric
chemical_list: D013193:Stainless Steel