Effect of mobile phone use on metal ion release from fixed orthodontic appliances

Am J Orthod Dentofacial Orthop. 2015 Jun;147(6):719-24. doi: 10.1016/j.ajodo.2015.01.023.


Introduction: The aim of this study was to evaluate the effect of exposure to radiofrequency electromagnetic fields emitted by mobile phones on the level of nickel in saliva.

Methods: Fifty healthy patients with fixed orthodontic appliances were asked not to use their cell phones for a week, and their saliva samples were taken at the end of the week (control group). The patients recorded their time of mobile phone usage during the next week and returned for a second saliva collection (experimental group). Samples at both times were taken between 8:00 and 10:00 pm, and the nickel levels were measured. Two-tailed paired-samples t test, linear regression, independent t test, and 1-way analysis of variance were used for data analysis.

Results: The 2-tailed paired-samples t test showed significant differences between the levels of nickel in the control and experimental groups (t [49] = 9.967; P <0.001). The linear regression test showed a significant relationship between mobile phone usage time and the nickel release (F [1, 48] = 60.263; P <0.001; R(2) = 0.577).

Conclusions: Mobile phone usage has a time-dependent influence on the concentration of nickel in the saliva of patients with orthodontic appliances.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Analysis of Variance
  • Cell Phone*
  • Dental Alloys / chemistry*
  • Dental Alloys / radiation effects
  • Electromagnetic Radiation
  • Female
  • Humans
  • Linear Models
  • Male
  • Nickel / analysis*
  • Nickel / radiation effects
  • Orthodontic Appliances*
  • Radiation Dosage
  • Saliva / chemistry*
  • Sex Factors
  • Spectrophotometry, Atomic / methods
  • Time Factors
  • Young Adult


  • Dental Alloys
  • Nickel