title: Effect of soft drinks on the physical and chemical features of nickel-titanium-based orthodontic wires.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the effect of three popular soft drinks on the Young's modulus, hardness, surface topography and chemical composition of widely used nickel-titanium-based orthodontic wires.
  
  
  METHODS
  Thirty-two specimens (20 mm in length) were cut from the straight portion of pre-formed 0.019 × 0.025 inch Nitinol Heat-Activated archwires and randomly divided into four groups of eight specimens each: Group A1 (Coca Cola(®) regular); Group A2 (Santal(®) orange juice); Group A3 (Gatorade(®)); Group B (distilled, deionized water; dH(2)O). Each specimen was immersed in 10 ml of one of the soft drinks or dH(2)O, control, for 60 min, at 37°C. At the end of the soaking time, the Young's modulus and hardness were determined using a nanoindenter. Scanning Electron Microscope-Energy Dispersive Spectroscopy (SEM-EDS) was used to characterize the effects on the topography and chemical composition of the wires.
  
  
  RESULTS
  No statistically significant differences were found between the groups either in the Young's modulus or in hardness after the selected soaking protocol. Besides some surface colour changes, the topography and the chemical composition of the wires were not affected by the immersion in any of the chosen soft drinks.
  
  
  CONCLUSIONS
  These in-vitro results suggest that the consumption of soft drinks cannot be acknowledged as one possible reason for the degradation of the physical and chemical properties of heat activated nickel titanium orthodontic wires in patients undergoing fixed orthodontic treatment.
authors.affiliation: Department of Orthodontics, School of Dentistry, University of Bologna, Italy.
authors.forename: Serena Incerti
authors.initials: SI
authors.lastname: Parenti
authors.forename: Stefano
authors.initials: S
authors.lastname: Guicciardi
authors.forename: Cesare
authors.initials: C
authors.lastname: Melandri
authors.forename: Simone
authors.initials: S
authors.lastname: Sprio
authors.forename: Elena
authors.initials: E
authors.lastname: Lafratta
authors.forename: Anna
authors.initials: A
authors.lastname: Tampieri
authors.forename: Giulio Alessandri
authors.initials: GA
authors.lastname: Bonetti
mesh_terms: D000497:Alloys; D002253:Carbonated Beverages; D003343:Corrosion; D003722:Dental Alloys / Q000737:chemistry*; D055119:Elastic Modulus; D006244:Hardness; D008422:Materials Testing; D009532:Nickel; D009969:Orthodontic Wires; D011897:Random Allocation; D013499:Surface Properties; D014025:Titanium
chemical_list: D000497:Alloys; D003722:Dental Alloys; C013616:nitinol; D009532:Nickel; D014025:Titanium