title: Release of nickel and chromium ions in the saliva of patients with fixed orthodontic appliance: An in-vivo study.
abstract: BACKGROUND
  Various components of fixed orthodontic appliances are continuously interacting with saliva and other fluids in the mouth releasing various metal ions including nickel and chromium that can cause damaging effects if their concentration exceeds above the toxic dose.
  
  
  OBJECTIVE
  To determine and compare the level of nickel and chromium in the saliva of patients undergoing fixed orthodontic treatment at different time periods.
  
  
  METHODS
  The sample of saliva of 13 patients was taken at different time periods that is: Group 1 (before appliance placement), Group II, III, and IV (after 1-week, 1-month, and 3 months of appliance placement respectively). The fixed appliance comprised of brackets, bands, buccal tubes, lingual sheath, transpalatal arch and wires composed of Ni-Ti and stainless steel. The level of ions was determined using graphite furnace atomic absorption spectro-photometry. The data thus obtained were statistically analyzed using SPSS Statistical Analysis Software (Version 15.0).
  
  
  RESULTS
  Level of nickel and chromium in saliva was highest in Group II and lowest in Groups I for both the ions. On comparison among different Groups, it was statistically significant for all the groups (<0.001) except between Group III and Group IV.
  
  
  CONCLUSIONS
  The release of nickel and chromium was maximum at 1-week and then the level gradually declined. These values were well below the toxic dose of these ions. The results should be viewed with caution in subjects with Ni hypersensitivity.
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Babu Banarasi Das College of Dental Sciences, Lucknow, Uttar Pradesh, India.
authors.forename: Anoop
authors.initials: A
authors.lastname: Dwivedi
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Babu Banarasi Das College of Dental Sciences, Lucknow, Uttar Pradesh, India.
authors.forename: Tripti
authors.initials: T
authors.lastname: Tikku
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Babu Banarasi Das College of Dental Sciences, Lucknow, Uttar Pradesh, India.
authors.forename: Rohit
authors.initials: R
authors.lastname: Khanna
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Babu Banarasi Das College of Dental Sciences, Lucknow, Uttar Pradesh, India.
authors.forename: Rana Pratap
authors.initials: RP
authors.lastname: Maurya
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Babu Banarasi Das College of Dental Sciences, Lucknow, Uttar Pradesh, India.
authors.forename: Geeta
authors.initials: G
authors.lastname: Verma
authors.affiliation: Department of Analytical Chemistry, Indian Institute of Toxicology Research Centre, Lucknow, Uttar Pradesh, India.
authors.forename: R C
authors.initials: RC
authors.lastname: Murthy
keywords: Chromium; graphite furnace atomic absorption spectrometry; in-vivo; nickel; saliva; transpalatal arch