Immunoexpression Of Il-17, Il-6 And Il-1β In Primary Chronic Apical Periodontitis In Smokers And Non-Smokers.

OBJECTIVE To compare the immunoexpression of biomarkers IL-17, IL-6 and IL-1β in primary chronic apical periodontitis in smokers (S) and non-smokers (NS). MATERIALS AND METHODS Teeth with primary chronic apical periodontitis (CAP) indicated for extraction in 16 cigarette smokers and 16 NS were selected. Silanized sections of tissue were used for immunohistochemical analysis after being stained with hematoxylin and eosin for histopathological categorization. Subsequently, the images were analyzed with an optical microscope and each slide was subdivided into five high-magnification fields, with scores (0-2) being assigned according to the amount of staining for each antibody. RESULTS The qualitative analysis of IL-17 cytokine expression showed negative to focal expression in 5.8%, weak to moderate expression in 17.6% and strong expression in 76.4% of the smokers, and negative to focal expression in 78.5% and weak to moderate expression in 21.4% of the NS. IL-6 expression was negative to focal in 13.3%, weak to moderate in 53.3% and strong in 33.3% of the smokers, and negative to focal in 33.3%, weak to moderate in 25% and strong in 41.6% of the NS. IL-1β expression was weak to moderate in 87.5% and negative to focal in 12.5% of the smokers and negative to focal in 100% of the NS. Quantitative evaluation of the data by Mann-Whitney test showed a significant difference in the immunoexpression of Il-17 (p <0.0001) and IL-1β (p <0.0001) and no significant difference in the immunoexpression of IL-6 (p = 0.46) between the two groups (p <0.05). CONCLUSION The cytokines IL-17 and IL-1β were more highly expressed in smokers than non-smokers, while IL-6 expression was similar in the two groups.