OBJECTIVE: To examine the surface of the tongue, pharynx, and larynx of animals exposed to tobacco, by scanning electron microscopy. STUDY DESIGN: Experimental study. METHODS: A total of 20 rats were divided into 2 groups: GI (Control) consisted of 10 rats that received water and animal food ad libitum, and GII (Tobacco group) consisted of 10 rats that were exposed twice a day to smoke inhalation from 10 cigarettes 7 days a week for 260 days without any food restrictions. After 260 days, the aerodigestive segment was removed and fragments of the tongue, hypopharynx, and right vocal fold were immersed in 2.5% glutaraldehyde and prepared for scanning electron microscopy. RESULTS: The filiform lingual papillae of the tongues of animals in the Tobacco group were irregularly displayed, flattened, and adhered to each other. The hypopharynx mucosa was very irregular, thickened, rough, and showed increased superficial peeling. The mucosa of the vocal folds had deep furrows surrounding the cells. These alterations were not observed in the control group. CONCLUSION: Several changes in the tongue, pharynx, and larynx were observed in animals from the Tobacco group, confirming the harmful effects of smoking on respiratory and digestive epithelium.
