RESUMO
BACKGROUND: The present study was conducted to evaluate keratinization as well as nuclear and cytoplasmic changes of oral epithelial cells among smokers, opium addicts and non-smokers through exfoliative cytology technique. METHODS: Smears of buccal mucosa and mouth floor were collected from 300 males (100 smokers, 100 opium addicts and 100 non-smokers). The nucleus and cytoplasm sizes were determined using image analysis software. Data was analyzed with Mann-Whitney test and Student's t-test on SPSS version 13 statistical software. Statistical significance was defined as P < 0.05. RESULTS: The results revealed statistically significant differences in cellular and nuclear size and the nuclear/cytoplasmic ratio between smokers, opium addicts and non-smokers in different age groups. The mean size of the nucleus compared to that of cytoplasm was significantly higher in smokers and opium addicts compared to non-smokers after correction for age. CONCLUSION: The results of this study indicate different rates of epithelial cell keratinization in oral cavity among smokers, opium addicts and non-smokers. Also, our results suggest a possible relationship between the number of cigarettes per day, daily opium consumption and an increase in the rate of cellular proliferation of oral mucosal cells. The present study indicated a decrease in cellular diameter as well as an increase in nuclear diameter and nuclear/cytoplasmic ratio in smears taken from both smokers and opium addicts compared to non-smokers.