Genetic damage in exfoliated cells from oral mucosa of individuals exposed to X-rays during panoramic dental radiographies

Cytogenetic biomonitoring in children submitting to a complete set of radiographs for orthodontic planning

“…In contrast, with respect to genetic damage, radiographs caused cellular death, as indicated by a statistically significant difference (P 5 .007) between values before and after X-ray exposure, in agreement with the findings of other studies. 11,13,17,19 This result endorsed the notion that X-rays are cytotoxic, and based on the knowledge that cytotoxicity interferes with MN induction because some MNC are inevitably lost after a cytotoxic insult, 13 the lack of a mutagenic effect on this set of X-rays is confirmed.…”

“…However, despite higher radiation doses in our investigation, research with similar methodology with dental radiographs showed similar results compared to our study (ie, no mutagenic characteristic was evidenced by the MN test). 6,11,13,14,[17][18][19][20][21] Differences in radiation dose, frequency of exposition, type of cells evaluated, and site of collected cells may influence the results of the MN test. Some authors investigated patients undergoing radiotherapy five to six times per week over the course of 5-7-weeks 16,29 and others observed the effects of frequent occupational exposition to low doses of X-ray in radiation workers, 2,30 whereas some pointed out the results of only a single dental radiograph exposition.…”

“…With regard to the different cells employed in the MN assay, radiotherapy is shown to be a potent clastogenic agent in circulating lymphocytes and BEC of head-and-neck cancer patients, 16 but lymphocytes are more sensitive in detecting chromosome aberrations caused by anticancer drugs than are BEC. 25,28 Additionally, in the cytogenetic studies of dental radiograph effects, different sites were elected from which to collect buccal cells: buccal cheek mucosa, 11,13,14,21 the lateral border of the tongue, 17,21 and keratinized mucosa of the upper dental arch. 12 One of these studies 21 showed that the lateral border of the tongue is more sensitive to cytotoxic insult than is the cheek buccal mucosa.…”

“…Researchers 11,23 have called attention to nuclear changes other than MN that characterize cellular death and may increase the sensitivity of tests to detect genotoxicity. Thus, cytotoxic effects were investigated through the frequencies of karyorrhexis, karyolysis, and pyknosis.…”

“…9 Micronuclei arise from acentric fragments or whole chromosomes that are not included in the main nuclei of the daughter cells and can be induced by agents that cause chromosome breakage or affect the spindle apparatus 10 and can be used as a biomarker in buccal cells to evaluate the mutagenic effect of many agents, including ionizing radiation. 6,[11][12][13][14][15][16][17][18][19][20][21] Previous studies conducted by our research group have demonstrated that the panoramic X-ray is able to induce damage in the oral mucosa cells of children. 13 In this regard, it would be interesting to know if, and to what extent, children submitted to orthodontic radiographic protocol are a more sensitive group as a result of the use of X-ray in oral mucosa cells, particularly because there are no previous reports.…”