Radiation Measurements 39
(2005) 143-148
M. Zdravkova, B. Gallez and R.
Debuyst
A comparative in vivo and in
vitro L-band EPR study of irradiated rat incisors
L-band
EPR has the potential to measure the absorbed radiation dose in human
teeth inside the mouth (in vivo analyses). One crucial point in the
development of the method is to know if dosimetry evaluation carried
out in vivo after accidental exposures can be reliably based on
calibration curves built in vitro. The aim of the present work is to
specifically address this point. First, we compared L-band in vitro and
in vivo analyses in irradiated rat teeth and estimated the possible
loss in in vivo experiments due to rat movements and mouth proximity.
Second, the lower pair of rat incisors were analysed by L-band EPR
before and after irradiation ,
first on the living rat, then on the same dead rat, finally after
extraction of the teeth. X-band powder spectra were also taken after
crushing of the two teeth. Irradiations of dead rats and extracted
teeth were also carried out. Comparing L-band spectra obtained with
living rats and removed heads does not show any significant difference
due to possible small rat movements or breathing. Relative standard
deviations of the amplitudes of the dosimetric signal are quite high
(27–54%). Nevertheless, it seems to be a tendency to have higher
signals in irradiated extracted teeth than in irradiated animals.