Dentist № 2 (45) – 2022, pp. 46-52                                                                                           SCIENTIFIC PUBLICATION

The influence of low doses of ionizing radiation on the rats microscopic and morphometric characteristics of tooth germs in the prenatal period

N.N. Cheshko

MD, PhD, Associate Professor, Belarusian State Medical University, Minsk, Belarus

https://doi.org/10.32993/dentist.2022.2(45).7

ABSTRACT
The aim of the study. To reveal microscopic and morphometric changes of experimental animals tooth germsn in the prenatal period under general exposure to low doses of ionizing radiation.
Objects and methods. The study was carried out on albino rats of mongrel gregarious breeding. Pregnant female rats were exposed to chronic irradiation in the Institute of Radiobiology of the National Academy of Sciences of the Republic of Belarus using “Gammarid-192/120 unit” at 110 mR/h power of exposition from the 1st day of pregnancy untill the collection of material on the 20th day. The total dose absorbed by the fetuses was 0.47 Gy.
Results and discussion. . The design of the device is convenient to use and reliable in operation, allows you to Despite the exposure to low doses of ionizing radiation, further growth and differentiation of the tooth germs were observed. The atrophy and resorption of such provisional structures as the outer enamel epithelium and the pulp of the enamel organ increased; in general, the mitotic activity in the cells of the tooth germs was leveled; regeneration significantly improved, the damaging effect of ionizing radiation seemed to be reduced. Nevertheless, negative changes in the odontogenesis in the tooth germs of the experimental group of animals had remained by the 20th day of intrauterine development.
Conclusion. Under the influence of low doses of ionizing radiation, proliferative activity decreased, swelling, segmentation, and focal discomplexation of the cells of the dental lamina, outer and inner enamel epithelium were observed. In general, there was a delay in the differentiation of tooth germ cells cells of 20-day-old fetusesn of rats.

Keywords: odontogenesis, ionizing radiation, low doses, rat

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Correspondence to:  Е-mail: cheshko.nelli@mail.ru