The increase of dysplasia level in Wistar rats oropharyngeal mucosa exposed by sidestream cigarette smoke


Background: Sidestream cigarette smoke contains several elements that can trigger cancer. The risk of various types of cancer, such as oral cancer, will increase in the number of people exposed to sidestream cigarette smoke. Dysplasia is a histopathological change that shows abnormal activities in the normal epithelium. Examination of oral epithelial dysplasia is vital in predicting the development of malignancy. This study aimed to determine the risk of malignant transformation in the oropharynx of Wistar rats (Rattus norvegicus) exposed to sidestream cigarette smoke through the observation of the degree of dysplasia in the oropharyngeal mucous in the 4th and eighth weeks after the exposure began.
Method: Wistar rats were divided into three groups, namely treatment group one, exposed to cigarette smoke for four weeks; treatment group two, exposed to cigarette smoke for eight weeks; and a control group that was not exposed to cigarette smoke. Oropharyngeal mucous of rats from each group were examined histopathologically to find the degree of dysplasia based on 2005 WHO classification. Degrees of dysplasia were treated quantitatively and analyzed statistically.
Results: A significant increase in the degree of dysplasia was found more in the treatment group 2 than in the control group. A significant increase in the degree of dysplasia was also found in treatment group 1 compared to the control group.
Conclusion: The oropharyngeal mucosa of Wistar rats exposed to sidestream cigarette smoke for four weeks and eight weeks experienced an increase in the degree of dysplasia.


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