[Precancerous lesions of the mouth mucosa in workers exposed to ionizing radiation].

Oral cavity tissues were examined in 398 persons aged 20 to 60 working with ionizing radiation sources (gamma-defectoscopists, x-ray technicians and radiologists). 222 persons worked with ionizing radiation for 1-10 yrs, 176 for 11-25 yrs. They were compared with 203 controls who had not been subjected to occupational irradiation. In all the cases radiation exposure doses did not exceed maximum permissible levels. Stomatological examination of the study group revealed a high prevalence of precancerous changes of the oral mucosa in men only. They were usually manifested in disturbance of keratinization of leukoplakia type. Tobacco smoking can play a certain role in the development of such changes of the oral mucosa in persons subjected to chronic radiation exposure. A further study of the stomatological status in persons of the above occupational group was found necessary.