title: Nickel and chromium levels in the saliva of patients with fixed orthodontic appliances.
abstract: OBJECTIVE
  The purpose of this study was to investigate the salivary concentration of nickel and chromium of patients undergoing orthodontic treatment.
  
  
  METHODS
  In this study 32 patients who presented to the orthodontic clinic were selected. The salivary samples were taken from the patients in four stages: before appliance placement and 20 days, 3 months, and 6 months following appliance placement. The salivary samples were collected in a plastic tube and were stored in the freezer before analysis. The samples were then transferred to the laboratory, and the amounts of metals were determined by graphite furnace atomic absorption spectrometry with an autosampler. Each sample was analyzed three times, and the average was reported.
  
  
  RESULTS
  It was found that the average amount of nickel in the saliva 20 days after appliance placement was 0.8 μg/L more than before placement. Also, the amount of salivary nickel 20 days after the appliance placement was more than at the other stages, but the differences were not significant. The average amount of chromium in the saliva was found to be between 2.6 and 3.6 μg/L. The amount of chromium at all stages after appliance placement was more than before, but the differences between the chromium levels of saliva at all stages were not significant.
  
  
  CONCLUSIONS
  There was no significant difference in the average amount of salivary nickel and chromium of patients at various stages of orthodontic appliance placement.
authors: Department of Orthodontics, Faculty of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. syassaei@yahoo.com
authors: Soghra
authors: S
authors: Yassaei
authors: Shayesta
authors: S
authors: Dadfarnia
authors: Hakima
authors: H
authors: Ahadian
authors: Farshad
authors: F
authors: Moradi
mesh_terms: D000293:Adolescent; D002648:Child; D002857:Chromium / Q000032:analysis*; D015331:Cohort Studies; D003722:Dental Alloys / Q000737:chemistry; D005500:Follow-Up Studies; D006801:Humans; D009532:Nickel / Q000032:analysis* / Q000737:chemistry; D016382:Orthodontic Appliance Design; D016910:Orthodontic Brackets; D009969:Orthodontic Wires; D012463:Saliva / Q000737:chemistry*; D013054:Spectrophotometry, Atomic / Q000379:methods; D013193:Stainless Steel / Q000737:chemistry; D014025:Titanium / Q000737:chemistry; D055815:Young Adult
chemical_list: D003722:Dental Alloys; D002857:Chromium; C040654:titanium nickelide; D013193:Stainless Steel; D009532:Nickel; D014025:Titanium