RESUMO
AIM: To evaluate the presence of metal ions and deoxyribonucleic acid damage on the cells of buccal mucosa in subjects scheduled to undergo fixed orthodontic treatment. MATERIALS AND METHODS: Eighty patients scheduled to undergo orthodontic treatment were included in the present study. Samples were collected from buccal mucosa of the subjects at five different intervals: before the starting of the fixed appliance therapy, 5 months after the insertion of the appliance, 10 months after insertion of the appliance, 15 months after insertion of the appliance and 20 months after insertion of the appliance. Flow cytometry was further used for assessment of apoptosis. Comet assay was used for evaluating the metal ions associated deoxyribonucleic acid ((DNA) damage of buccal epithelial cells. Atomic absorption spectrometry was used for measuring the nickel (Ni), chromium (Cr) and zinc (Zn) levels in the cells of the buccal mucosa. Analysis of data was done by SPSS software version 16.0. RESULTS: A significant increase in the Ni, Cr and Zn concentra -tion during orthodontic treatment was observed. A progressive non-significant decrease in the percentage of viable cells from a baseline value to the end of the treatment was observed. A significant increase in the head diameter, DNA in tail and tail length, starting from the pretreatment value to the end of orthodontic treatment, was also observed. CONCLUSION: Timely checking of deoxyribonucleic acid (DNA) damage and nuclear changes should be done for detecting earlier adverse changes. CLINICAL SIGNIFICANCE: In patients wearing orthodontic appliances, no clinical impact occurs by wearing fixed appliances.
