Evaluation of Genotoxic Effects of Panoramic Dental Radiography on Cells of Oral Mucosa by Micronucleus Assay and Evaluation of Time Period Required by Cells of Oral Mucosa to Recover from the Genotoxic Effects
Citation Information :
Kaur I, Sheikh S, Pallagati S, Gupta D, Singh R, Aggarwal A, Mago J. Evaluation of Genotoxic Effects of Panoramic Dental Radiography on Cells of Oral Mucosa by Micronucleus Assay and Evaluation of Time Period Required by Cells of Oral Mucosa to Recover from the Genotoxic Effects. World J Dent 2020; 11 (1):17-23.
Aim: To evaluate the genotoxic effects of X-rays on epithelial cells during panoramic dental radiography on the cells of the oral mucosa by micronucleus assay. It also aimed to evaluate the time period required by the cells of the oral mucosa of these patients to recover from these genotoxic effects. Materials and methods: Patients were divided into two age groups. Group I included subjects aged from 15 years to 25 years, while group II included subjects 40 to 50 years of age. Each group had 50 subjects. The histopathological sample was obtained with the help of a wooden spatula in both keratinized and non-keratinized mucosa pre-exposure, 10th day and 21st day post-exposure, respectively, and micronuclei were calculated. Results: There was a statistically significant increase in micronuclei on 10th day and a statistically significant decrease in micronuclei on 21st day post-exposure in both keratinized and non-keratinized mucosa and when compared with pre-exposure. It revealed more marked effect on keratinized mucosa. Furthermore, in group II, no statistically significant differences were noted at the time of pre-exposure and on the 10th day post-exposure as well as on the 21st day post-exposure. Conclusion: Genotoxic effects do take place due to panoramic radiography; it has also been seen that these genotoxic effects are reversible as these cells tend to recover from the effects. Clinical significance: Since radiography is an integral part of day-to-day dental practice and patients are frequently exposed to panoramic radiography, it is emphasized that panoramic radiography may be done only when necessary after weighing the benefits against the risks. X-rays being ionizing radiation are well known as mutagens and carcinogens in the human population. Thus, it becomes important that to detect the radiation effects of low-dose diagnostic radiographic exposures, a sensitive analysis and specific approach is needed.
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