Dental amalgam, causes perturbation in photon dose distribution of head and neck (H&N) radiotherapy. The aim of this study was to evaluate the effects of dental amalgam on dose distribution of H&N radiotherapy and accuracy of dose calculations algorithm of commercial treatment planning system (TPS). In this study, the measurements were performed using a constructed H&N anthropomorphic. The sample of healthy teeth and teeth filled by amalgam inserted in the desired segment of the phantom in turn. After scanning and organs segmentation of phantom, intensity-modulated radiation therapy (IMRT) plan including 7 fields in the absence (plan 1) and presence (plan 2) of dental amalgam were created separately. Phantom was irradiated using 6 MV linear accelerator (SIMENS-ARTISTE, 5918). Assessment of the effects of dental amalgam on dose distribution and the accuracy of dose calculation algorithm of TPS was done by measurement and comparing of organ's received dose using thermoluminescent dosimeter (TLDs), placed on a phantom and TPS calculations. The scattering and attenuation due to the presence of dental amalgam led to an increase in parotid glands received dose (up to 24.38%) and a decrease in mean dose (up to −6.25%) PTV70. Results of this study revealed that discrepancies between the collapsed cone convolution (CCC) algorithm calculations Prowess Panther TPS and TLD measurements were −19.77% to 27.49% in presence of amalgam and −1.09% to 5.03% in presence of healthy teeth in phantoms. Attenuation and scattering due to amalgam in IMRT of H&N cancer may lead to a significant dose perturbation which is not predictable by dose calculation of TPS.

牙科用汞合金会引起头颈（H＆N）放射治疗的光子剂量分布扰动。这项研究的目的是评估牙科汞合金对H＆N放射治疗剂量分布的影响以及商业治疗计划系统（TPS）剂量计算算法的准确性。在这项研究中，使用构造的H＆N拟人模型进行了测量。健康牙齿和由汞齐填充的牙齿的样本依次插入到人体模型的所需部分中。在对人体模型进行扫描和器官分割后，分别创建了强度调制放射治疗（IMRT）计划，该计划包括不存在（计划1）和存在（计划2）牙科汞合金的7个场。使用6 MV线性加速器（SIMENS-ARTISTE，5918）照射幻影。通过使用幻影剂量计（TPD）测量和比较器官的接收剂量，并通过幻像和TPS计算，评估牙科用汞合金对剂量分布的影响以及TPS剂量计算算法的准确性。由于存在牙科用汞合金而导致的散射和衰减导致腮腺接收剂量增加（高达24.38％），平均剂量下降（高达-6.25％）。这项研究的结果表明，折叠汞卷积（CCC）算法计算的Prowess Panther TPS和TLD测量值之间的差异在使用汞合金的情况下为-19.77％至27.49％，在使用健康牙齿的幻象中为-1.09％至5.03％。H＆amp;的IMRT中由于汞齐引起的衰减和散射