In vitro evaluation of head and neck radiation shields used to reduce exit dose.

Autor: Dirican B, Ozen J, Beyzadeoglu M, Oysul K, Surenkok S, Sipahi C
Zdroj: International Journal of Prosthodontics; Sep/Oct2006, Vol. 19 Issue 5, p462-466, 5p
Abstrakt: PURPOSE: To determine the optimal thickness of protective oral radiation shields composed of an acrylic resin stent and a lead shield, which are used in head and neck radiotherapy to minimize undesired normal tissue radiomorbidity. MATERIALS AND METHODS: Intraoral acrylic resin stents and lead shields of different thicknesses were inserted into a specially designed human mandible phantom with thermoluminescent lithium fluoride dosimeter chips (TLD-100) placed on the buccal and lingual sites and exposed to irradiation of different energies. Fifty-cGy irradiation was performed and TLD-100 dose measurements were obtained for each irradiation type, acrylic resin stent thickness, and lead shield thickness. RESULTS: Acrylic resin stents with a 2-mm lead shield reduced 20% and 15% of the normal tissue dose for Co-60 and 6 MV X photon radiations, respectively, whereas the stents with a 4-mm lead shield achieved a higher reduction of the normal tissue dose (30% and 23% for Co-60 and 6 MV X photons, respectively). CONCLUSION: In protective oral radiation shields, acrylic resin stent thickness has little effect on the reduction of normal tissue dose, but lead shield thickness significantly effects the reduction of normal tissue dose. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index