Journal of AdvancedMedical and Dental Sciences Research

Background: The elevated levels of metals in saliva are thought to occur by corrosion of the chemical elements in the alloys or welding materials. The aim of this study was to evaluate the concentrations of nickel and chromium ions in salivary samples from patients treated with fixed orthodontic appliance. Materials and Methods: This retrospective study was carried out on 23 subjects (13 females and 10 males) who had undergone fixed orthodontic therapy for a duration of 12–18 months. A same-gender brother or sister (total of 23 subjects) was selected as a control in order to limit the effects of dietary and hygiene habits on salivary metal ion concentration. Approximately 5 ml of saliva was collected from each subject, and the samples were analysed using an atomic absorption spectrophotometer. The detection limit of the method for sample solutions was 1 ng/ml. Since some variables were not normally distributed, non-parametric tests (Mann–Whitney U and Wilcoxon W) were used for statistical analysis. Results: The mean salivary nickel (Ni) content in subjects with and without a fixed orthodontic appliance was 17.1-12.1 and 11.7-10.6 ng/ml in the subjects and controls, respectively. A statistically significant difference (P < 0.035) was found between the two groups. The mean salivary chromium (Cr) ion level recorded was 2.3-1.7 in the controls and 1.6 -1.3 ng/ml in the study group. The difference, however, was statistically insignificant. Conclusion: Within the limits of this in vivo study, it can be concluded that the presence of fixed orthodontic appliances leads to an increased concentration of metal ions in salivary secretions. Key words: Metallic ions, fixed appliances, saliva.