title: Mechanical properties of cobalt-chromium wires compared to stainless steel and β-titanium wires.
abstract: BACKGROUND
  Previous studies have reported on mechanical properties of different orthodontic wires. However, there is a paucity of information that comparing the mechanical properties of Blue Elgiloy (BE) when compared to stainless steel and TMA, as finishing wires as received by different companies.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the mechanical properties of BE wires compared to stainless steel (SS) and titanium Molybdenum alloy (TMA) also known as β titanium as provided by two companies.
  
  
  METHODS
  Six 0.016 x 0.022-14mm-samples of each wire were fixed individually to Instron machine and were tested in loading and unloading for three times. The initial load was set for 500 Kg at a speed of 1mm/min and displacement was adjusted for (0.5, 1mm in loading and 0.5 mm unloading at 25°C).
  
  
  METHODS
  Variables were compared between groups by ANOVA test using SPSS statistical software.
  
  
  RESULTS
  BE shows comparable forces to SS when loaded 0.5 and showed decreased forces in 1mm loading compared to SS, and higher than TMA. BE also showed no forces at unloading and high deformation.
  
  
  CONCLUSIONS
  BE from the two companies showed comparable mechanical properties while SS and TMA were different. The deformation of BE and its decreased forces in unloading may limit its clinical use.
authors.affiliation: PhD Student, Universitätsklinikums, Bonn, 53111, Germany.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Alobeid
authors.affiliation: Department of Physics, Faculty of Sciences, Aleppo, Syria.
authors.forename: Malak
authors.initials: M
authors.lastname: Hasan
authors.affiliation: Faculty of Dentistry, University of Aleppo, Aleppo, Syria.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Al-Suleiman
authors.affiliation: Division of Orthodontics, School of Dentistry, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, T6G 2E1, Canada.
authors.forename: Tarek
authors.initials: T
authors.lastname: El-Bialy
keywords: Blue Elgiloy; mechanical properties; orthodontic wire; stainless steel; titanium-molybdenum alloy