RESUMEN
There are only few studies about effect of chemoradiotherapy based on cellular level. The aim of this study was to evaluate the effects of such treatment on normal cells of oral mucosa. Seventy patients whose normal oral mucosa was exposed to radiation during the course of chemoradiotherapy were selected. Before starting the treatment, 2 slides from the normal oral mucosa were prepared for each patient, one from keratinized and one from non keratinized mucosa. At the end of treatment 2 other slides were taken from the same area too. After observing the slides under light microscope in blind form, the results of the observation from the first slides were compared with the results of the second one. Statistical analysis was carried out by Mc Nemar, Marginal Homogeneity and Wilcoxon tests. The results revealed changes in nucleus and cytoplasm. and N/C ratio, formation of bizar cells, cellular abnormality, nucleous and cytoplasmic vacuolization in affected cells during treatment. There was statistically significant differences between the groups [p < 0.001]. Keratinization of basal cell mucosa in cytology slide was observed after treatment [P < 0.01] and also there was an increase in number of inflammatory cells [p < 0.001]. Cellular apoptosis, numerous granular cells with large size granules, cells with multiple nucleous and clear nuclei, bacterial colony and candida were observed after treatment. chemoradiotherapy may induce formation of bizar cells, abnormal nocleous and cytoptasm, changes in N/C ratio. Cellular abnormality, and cellular vacuolization