Genotoxicity and Cytotoxicity of X-rays in Children Exposed to Panoramic Radiography

OBJECTIVE To assess the genotoxicity and cytotoxicity produced by X-rays in the epithelium of the oral mucosa of infants exposed to panoramic radiography. METHODS The sample consisted of 30 healthy children, 19 females and 11 males, ranging in age from 4 to 10 years (average of 7 years of age). Oral mucosa cells were collected by liquid-based cytology immediately before and after seven days following the exposure to panoramic radiography. Smears were processed and stained using the modified Feulgen Rossenbeck technique. Bud and broken egg nuclear projections, changes in the form of micronuclei, and genotoxic and cytotoxic changes of pyknosis, karyorrhexis and karyolysis were analyzed and quantified. RESULTS The frequency of pyknosis, buds and broken eggs was significantly higher after exposure to X-rays (p<0.05), but there was no statistically significant difference regarding gender, as well as in the other changes studied. CONCLUSIONS Exposure to X-rays emitted during submission to panoramic radiography may induce cell death in the epithelium of children's oral mucosa. No evidence was found for a significant genotoxic effect.