Projects / Programmes
Investigation of oxidative stress occurrence, causes and harmful effects induced by the use of fixed orthodontic appliances
| Code |
Science |
Field |
Subfield |
| 3.02.00 |
Medical sciences |
Stomatology |
|
| Code |
Science |
Field |
| 3.02 |
Medical and Health Sciences |
Clinical medicine |
orthodontic treatment with fixed appliances, oxidative stress, oxidative damage, metal ions
Researchers (14)
Organisations (3)
Abstract
Fixed orthodontic appliances used for treatment of orthodontic and jaw anomalies are mainly made of stainless steel and nickel-titanium alloys. Orthodontic appliances are usually in the oral cavity for long periods of time, therefore are exposed to degradation processes. Metal alloys in the oral cavity are subjects concomitantly to corrosion (due to the electrolyte medium-saliva) and mechanical load for example due to masticatory forces, during orthodontic treatment also due to the sliding of the archwire along the bracket's slot. Due to the concomitant effects of corrosion, deformation, friction and mechanical load on fixed orthodontic appliances during treatment, degradation of orthodontic brackets and archwires occurs, which might induce higher concentrations of metal ions in the oral cavity. Metal ions have either smaller or larger toxic effects on the tissues of the oral cavity or even systemic effects when absorbed and entered in the systemic blood circulation. Several transition metals has unpaired electrons, this enables the formation of reactive oxygen species (ROS), and generation of oxidative stress through the Fenton-like reactions. Regarding the systemic level of oxidative stress in capillary blood during treatment with fixed orthodontic appliances, we found a transient increase of systemic oxidative stress level 24 hours after the insertion of appliances and a decrease 7 days after their activation. Causes and mechanisms for this phenomenon, that are not yet understood, will be studied in the proposed research project. Of course, ROS may affect cell and tissue damage in the local microenvironment more than on the systemic level. The role of ROS in gingival crevicular fluid in the pathogenesis of periodontal disease has been well studied, while the effects of orthodontic treatment on ROS formation in gingival crevicular fluid have not been fully explained. In the literature reviewed, we did not find much research examining the impact of fixed orthodontic appliances on the occurrence, causes, and adverse effects of oxidative stress on periodontal tissues and mechanisms of cellular injury. The aim of the research project is to investigate the causes and mechanisms responsible for oxidative stress induced damage related to exposure to metal ions released from fixed orthodontic appliances and to assess the associated health risks. Further objectives are to evaluate the possible effects of ROS on the occurrence of local damage of periodontal tissue by measuring the antioxidant potential of the gingival crevicular fluid among subjects with fixed orthodontic appliances made of different materials. Since metal ions released from corroded orthodontic appliances could induce oxidative stress, the mechanism of the effects of singular and different combinations of metal ions on ROS formation will be assessed on different cell lines. In particular, the concentrations of metal ions released from fixed orthodontic appliances in artificial saliva will be determined and the toxic effects of several metal ions from dental alloys (Fe, Ni, Cr, Co, Mo and Ti) and their different combinations will be tested on the model organism of Saccharomyces cerevisiae. Moreover, the toxicity of TiO2, ZnO in IF-WS2 nanoparticles on the cell line of human gingival fibroblasts will also be assessed. The clinical assessments will enable us to understand the physiologic reaction of periodontal tissue to orthodontic fixed appliances and to better explain the results on cellular level. The results will provide new knowledge whether the exposure to selected metal ions from fixed orthodontic appliances and their combinations not only causes oxidative stress but also leads to the formation of oxidative damage to DNA, proteins and lipids. By systematic literature review and according to the results of the proposed project and previous research complete health risk assessment will be carried out.
