Pregnant mothers were irradiated by a single dose of gamma rays
(٠،٢،٤،٦ Gy, Cobalt ٦٠) in the days ١٠،١٢،١٤،١٦،١٨ of pregnancy. The
heads of the embryos’, and those of the neonates were taken at
consecutive intervals of irradiation, starting from
١٦ days of pregnancy
till ٣rd day after delivery. The effect of irradiation was investigated in the
development of the ٢nd and ٣rd lower molars on serial tissue sections,
within consecutive periods of their organogenesis. Irradiation led to
growth-deficiency in the ٢nd & ٣rd molars, and caused delay in their
development. This was observed in various degrees depending on the
dose, time of irradiation, and time after irradiation.
Mice embryos were irradiated in utero by gamma rays (٠،٢،٤،٦ Gy) at
١٠،١٢،١٤،١٦،١٨ days of gestation. Histological study was carried out on the
first premandibular molar after ٢،٤،٦،٨ days of irradiation, to investigate the
effect of irradiation on different stages of molar development.
This study involved the irradiation of mouse embryos at different stages of
pregnancy, using dose of ٤ Gy γ-radiation, at ١٠, ١٢, ١٤ and ١٦ days of
pregnancy. Pregnant mice were killed after ٢, ٤ and ٦ days post irradiation.
Embryo’s heads were is
olated and serial cross sections were made to
investigate the effect of irradiation on the different components of the eye at
different periods of eye organogenesis.
It was proved from this study that irradiation causes microphtalmia and
decrease in the growth of lens, retina and corneal stroma, as well severe
disruption in its development and disfigurement in its hitogenesis. These
defects have shown great differences in their severity according to the age of
embryos at exposure and the number of days post irradiation.
