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Published on: July 15, 2020
Nucleolar organizer regions of oral epithelial cells in crack cocaine users
Magna Carvalho de M Thiele1, Joslei Carlos Bohn2, Cassiano Lima Chaiben2
1Dept. of Stomatology, Universidade Federal do Paraná - UFPR, Curitiba/PR Brazil.
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.
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