Assessment of MB2 Canal Location via CBCT analysis

Introduction: periodontal patients due to problems such as spacing, malalignment and protrusion may need orthodontic treatment .Oral characteristic in periodontal patients is different from healthy individuals. For instance, salivary PH of periodontal patients is lower than that of normal ones. Alteration in oral environment particularly fluctuation in PH could influence on ion release such as nickel and chromium from orthodontic appliances. But there has been no investigation in this area. The aim of this study was to assess the effect of periodontal disease on nickel and chromium ion release in patients under fixed orthodontic treatment. Methods: This in vivo study evaluated 40 patients in test (periodontal patients under fixed orthodontic treatment) and control (healthy patients under fixed orthodontic treatment) groups (n=20). Patients with systemic disease or metal dental restorations, smokers, those taking medications and patients with mouth breathing were excluded. Two months after the onset of fixed orthodontic treatment, saliva samples were collected from both groups (with similar nutritional and oral hygiene status) and after dilution, the amount of nickel and chromium ions in the saliva was quantified using inductively coupled plasma mass spectrometry. The values were compared between the two groups using the Mann-Whitney U test and t-test. Results : The salivary level of nickel was 338±235 ppb and 183±116 ppb in the test and control groups, respectively, which was 156 ppb or 85% higher in the test group. According to the Mann Whitney U test, this difference was statistically significant (P<0.001). The salivary level of chromium was 7.4±3.15 ppb in the test and 6.35±2.39 ppb in the control group, which was 1.1 ppb or 17.3% higher in the test group. According to t-test, this difference was not significant (P=0.2). Conclusion : Within the limitations of this study, it appears that the salivary level of nickel significantly increases in orthodontic patients with periodontitis compared to controls at 2 months following the onset of orthodontic treatment.