Abstract

Background: Metal ions released from dental alloys pose a significant concern due to their potential local and systemic effects. One of these effects is hypersensitivity, particularly associated with nickel-containing dental alloys. Aims: to measure metal ion concentration in saliva during orthodontic space closure on a 0.019X0.025 working archwire. Material and Methods: Trial design: Controlled clinical trial Setting: Orthodontic treatment was provided at the Postgraduate Orthodontic Teaching Clinics and saliva testing was performed at the Faculty of Chemical Engineering/ Jordan University of Science and Technology (JUST). Methods Participants and interventions: Twenty-eight participants with bimaxillary proclination requiring extraction of all first premolar teeth participated in this study. Teeth alignment started with 0.014-inch nickel titanium (NiTi) archwire, then with a sequence of 0.018-inch, 0.016X0.022-inch, and 0.019X0.025-inch NiTi archwires, before 0.019X0.025-inch Stainless Steel (SS) rectangular archwire was reached. Patients were monitored monthly for a period of three months. Three unstimulated saliva samples were collected from each patient; before the commencement of treatment (T0), when 0.019X0.25-inch SS archwire was reached before space closure (T1), and one month after space closure (T2). Ion concentration in saliva samples was measured using an inductively coupled plasma mass spectrometer (ICP-MS). Results: Before treatment, iron concentration (53 Fe and 54 Fe) averaged 197.05 (64.35) mg/L and 425.48 (164.43) mg/L, respectively. Iron concentration increased during the alignment stage of orthodontic treatment (P<0.05) with no significant increase during space closure (P>0.05). Other investigated ions (Cr, Co, Ni, and Ti) did not show significant changes during orthodontic treatment (P>0.05). Conclusions: There was no increase in the metal ions concentration (Fe, Cr, Ti, and Ni) during space closure using a 0.019X0.025 working archwire and the Fe ion concentration increased in the initial stages of orthodontic treatment.