Nucleolar organizer regions of oral epithelial cells in crack cocaine users.

BACKGROUND The health risks of crack cocaine smoking on the oral mucosa has not been widely researched and documented. OBJECTIVE The purpose of this study was to analyze the proliferative activity of oral epithelial cells exposed to crack cocaine smoke using silver nucleolar organizer region (AgNOR) staining. METHODS Oral smears were collected from clinically normal-appearing buccal mucosa by liquid-based exfoliative cytology of 60 individuals (30 crack cocaine users and 30 healthy controls matched for age and gender) and analyzed for cytomorphologic and cytomorphometric techniques. RESULTS Crack cocaine users consumed about 13.3 heat-stable rocks per day and the time consumption of the drug was of 5.2 (± 3.3) years. Mean values of AgNOR counting for case and control groups were 5.18 ± 1.83 and 3.38 ± 1.02 (P<0.05), respectively. AgNOR area and percentage of AgNOR-occupied nuclear area were increased in comparison with the control (P<0.05). There was no statistically significant difference in the mean values of the nuclear area between the groups (P>0.05). CONCLUSION This study revealed that crack cocaine smoke increases the rate of cellular proliferation in cells of normal buccal mucosa.