title: Effect of saliva on load-deflection characteristics of superelastic nickel-titanium orthodontic wires.
abstract: OBJECTIVE
  Most published results about the characteristics of NiTi wires are based on the mechanical laboratory tests on the as-received wires.The purpose of this study was to investigate the effect of saliva on load-deflection characteristics of superelastic NiTi wires.
  
  
  METHODS
  In this experimental study, 15 wires of three kinds of superelastic NiTi wires (Sentalloy, Force I and Truflex) were prepared. Five specimens of each wire were tested in the as-received condition (T0) to provide baseline information and the remaining wires were divided into two groups of five. Half of them were kept inside artificial saliva for one month (T1), while the others were kept in air (T2). After 30 days, three-point bending test was done in a dental arch model and data from selected points on the unloading phase of the generated graphs were used for statistical analysis.
  
  
  RESULTS
  Force I and Truflex showed significantly greater force than Sentalloy. The load values of Truflex and Force I after one month exposed to artificial saliva (T1) decreased significantly, but Sentalloy was not affected significantly. The plateau gap values were not considerably different among T0, T1 and T2.
  
  
  CONCLUSIONS
  Saliva decreased the load of Force I and Truflex significantly, but it did not have a statistically significant effect on Sentalloy.
authors: Professor, Department of Orthodontics, Faculty of Dental Research Center and Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
authors: T
authors: T
authors: Hosseinzadeh Nik
authors: H
authors: H
authors: Ghadirian
authors: M Nili
authors: MN
authors: Ahmadabadi
authors: T
authors: T
authors: Shahhoseini
authors: M
authors: M
authors: Haj-Fathalian
keywords: Artificial Saliva; Superelastic NiTi Wires; Three-Point Bending