Experimental study of the influence of dental restorations on thermal and fast photo-neutron production in radiotherapy with a high-energy photon beam.
Appl Radiat Isot
; 147: 113-120, 2019 May.
Article
em En
| MEDLINE
| ID: mdl-30870764
ABSTRACT
In head and neck radiation therapy, the presence of dental restorations can increase unwanted neutron dose to the patient. This study aimed at the measurement of secondary neutron production induced by irradiation of a healthy tooth, Amalgam, Ni-Cr alloy and Ceramco with a photon beam generated in the treatment head of a Siemens Primus linac at a voltage of 15â¯MV. The irradiation field amounted to 10â¯×â¯10â¯cm2. The measurements of thermal and fast-neutron equivalent doses were performed by means of CR-39 detectors positioned in various depths of a Perspex (polymethyl methacrylate) phantom as at open field as at presence of corresponding dental restorations. The general trend of thermal neutron as well as fast-neutron equivalent dose behind the denture samples reveals their reduction with increasing depth. The maximum values of thermal-neutron dose related to Amalgam, Ceramco and Ni-Cr alloy amount to 1.45 mSv/100 MU, 1.38 mSv/100 MU and 1.32 mSv/100 MU, whereas the corresponding maximum values of fast-neutron dose at the depth of 1.8â¯cm amount to 0.19 mSv/100 MU, 1.04 mSv/100 MU and 0.97 mSv/100 MU, respectively. The present study investigates the neutron dose accompanied with radiotherapy. It is recommended that attempts have to be made to ensure that dental restorations are not in the path of the primary high-energy photon beam. Considering treatment planning, the guidelines of radiation protection should be improved.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Radioterapia
/
Fótons
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Restauração Dentária Permanente
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Nêutrons Rápidos
Tipo de estudo:
Guideline
Limite:
Humans
Idioma:
En
Revista:
Appl Radiat Isot
Ano de publicação:
2019
Tipo de documento:
Article