Dental tissue as a TLD dosimeter

ABSTRACT

Thermoluminescence dosimetry is one of the dosimetry procedures used widely as routine and personal dosimeters. In order to extend this kind of dosimeters, dental tissue has been examined and was found promising as a TLD dosimeter. Materials and In this study, 70 health teeth were collected. The only criterion, which was considered for selection of the teeth, was the healthiness of them regardless of age and gender of the donors. All collected samples were washed and cleaned and milled uniformly. The final powder had a uniform grain size between 100 - 300 micrometer. The sample was divided into four groups. Group A and B were used for measurement of density and investigation of variation of thermoluminescent characteristics with temperature respectively. Groups C and D were used for investigation of variation of thermoluminescent intensity with dose and fading of this intensity with time. In all cases the results obtained with dental tissue were compared to a standard LiF, TLD dosimeter. It was found that, average density of the dental tissue was 1.570 g/cm3, which is comparable to density of LiF, which is 1.612 g/cm3. It was also concluded that the range of 0-300°C, dental tissue has a simple curve with two specific peaks at 140 and 250°C respectively. The experiment also showed that, the variation of relative intensity versus dose is linear in the range of 0.04 - 0.1Gy. The fading rate of dental tissue is higher than LiF but still in the acceptable range [14% per month in compare to 5.2% per month] Dental tissue as a natural dosimeter is comparable with TLD and can be used in accidental events with a good approximation