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.
