Calculation of absorbed doses of photon and neutron radiations in tooth enamel and dentin by Monte Carlo method

«Radiation and Risk», 2015, vol. 24, No. 2, pp.93-106

Authors

Khailov A.M. – Senior Researcher, C. Sc., Biol. A. Tsyb MRRC, Obninsk, Russia. Contacts: 4 Korolyov str., Obninsk, Kaluga region, Russia, 249036. Tel. (484) 399-71-48; e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
Ivannikov A.I. – Lead. Researcher, C. Sc., Phys.-Math. A. Tsyb MRRC, Obninsk, Russia.
Orlenko S.P. – Researcher. A. Tsyb MRRC, Obninsk, Russia.
Borysheva N.B. – Senior Researcher, C. Sc., Phys.-Math. A. Tsyb MRRC, Obninsk, Russia.
Skvortsov V.G. – Head of Lab., C. Sc., Biol. A. Tsyb MRRC, Obninsk, Russia.

Abstract

Absorbed doses in tooth tissues – enamel and dentin, as well as in various organs of a human body from external irradiation by neutrons with energies between 10-9 and 20 MeV and photons with energies between 0.05 and 10 MeV in six standard geometries were calculated with the use of Monte Carlo method (program MCNP-4С). Modified mathematical MIRD phantom supplied with detailed dental area containing a description of 32 teeth was used to model the irradiation of a human body. Verification based on comparison of calculated doses to various organs with the data from literature sources demonstrated a good coincidence, for fast neutrons and photons the discrepancies were less than 7%. This paper also presents formulas for calculating conversion coefficients from neutron doses and photon doses absorbed in enamel or dentin to organ doses and effective dose in the body. The dose values calculated could be used to assess the individual doses and dose distribution in the body of the victims based on values of the doses in tooth dentin and enamel defined by EPR spectroscopy and available information about radiation incident.

Key words
EPR spectroscopy, retrospective dosimetry, tooth dentin, tooth enamel, Monte Carlo method, mathematical phantom, neutron radiation, individual dose, mixed radiation, dose conversion coefficients.

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Full-text article (in Russian)