A cytopathological study of the effect of smoking on the oral epithelial cells in relation to oral health status by the micronucleus assay


Background: Micronucleus is a cytoplasmic fragment of DNA reported as a biomarker of cancer. It is a cytoplasmicchromatin mass formed in the basal cells layer of the epithelium. These fragments can form their own membrane. Theaims of the study was to detect the micronuclei expression in the oral epithelial cells in cytopathological smears ofthe non-smokers’ and the smokers’ males, correlate the micronuclei expression in the oral epithelial cells with the oralhealth status variables, and evaluate the efficacy of the micronuclei assay to detect the subjects at high risk of oralmutations.Materials and methods: This study was conducted on 75 males of (35- 40) years of age divided into 25 heavy smokers,25 light smokers, and 25 non-smokers. A cytobrush was used to obtain the smears. The oral health status wasevaluated by using the plaque, gingival, calculus indices in addition to the amalgam and composite restorations.Results: There was a statistically significant difference in the micronuclei expression among the three groups. Therewas a strong correlation between the oral health status variables and the micronuclei expression in the non- smokers'group, for the Plaque index with (P-value =0.0005) and for the calculus index (P-value = 0.04). The smokers' group hada strong correlation with the amalgam restorations with (P-value =0.0005).Conclusion: The micronucleus assay detected by Pap stain is a useful biomarker to detect the people at high risk oforal mutations due to the harmful effect of the smoking, the calculus and plaque indices, in addition to theamalgam restorations