Iman Yarmohammadi - Graduated from Faculty of Dentistry, Shahed University, Tehran, Iran
Noushin Jalayer Naderi - Department of Oral and Maxillofacial Pathology, Faculty of Dentistry, Shahed University, Tehran, Iran

Background: Different histochemical stains have been applied to demonstrate the cytotoxic and genotoxic effects of cigarette smoking on cells. Feulgen and Papanicolaou were the most popular stains to demonstrate nuclear abnormalities. The aim of this study was to compare Feulgen and Papanicolaou stains in demonstrating the cytotoxic and genotoxic effects of cigarette smoking on exfoliated oral mucosa cells. Methods: A total of ۳۱ cigarette smokers and ۱۵ non-smokers were included in this case-control study. Using a wooden spatula, two samples were taken from each participant. The samples from the left buccal mucosa were stained with Feulgen and the right mucosa with Papanicolaou. The mean number of micronuclei and the number of cells with pyknosis, karyorrhexis, and karyolysis were determined on Feulgen and Papanicolaou-stained slides. The number of counted cells with pyknosis, karyorrhexis, and karyolysis in ۱۰۰۰ cells/subject was recorded. The mean number of micronuclei was determined by the number of counted micronuclei per ۱۰۰۰ cells per subject. Results: The number of micronuclei was not significantly different between Feulgen and Papanicolaou stained samples (P = ۰.۲۷). Demonstration of karyolysis (P = ۰.۷۳) and karyorrhexis (P = ۰.۲۴) was not significantly different between Feulgen and Papanicolaou staining methods. The Feulgen was significantly more effective in demonstrating pyknosis compared to Papanicolaou (P = ۰.۰۲). Conclusions: Feulgen and Papanicolaou stains had similar effectiveness in demonstrating DNA alterations (micronucleus) and cellular death features (karyorrhexis and karyolysis). Feulgen was preferable to display pyknosis than Papanicolaou.

Assay, Buccal, Cytotoxicity, Micronucleus