@article{oai:repo.qst.go.jp:00084266, author = {Ikawa, Hiroaki and Inaniwa, Taku and Koto, Masashi and Bhattacharyya, Tapesh and Kaneko, Takashi and Takiyama, Hirotoshi and Shinoto, Makoto and Yamada, Shigeru and Tsuji, Hiroshi and Hiroaki, Ikawa and Taku, Inaniwa and Masashi, Koto and Bhattacharyya, Tapesh and Takashi, Kaneko and Hirotoshi, Takiyama and Makoto, Shinoto and Shigeru, Yamada and Hiroshi, Tsuji}, issue = {1}, journal = {Radiological physics and technology}, month = {Nov}, note = {In this study, the stopping-power ratios (SPRs) of mouthpiece materials were measured and the errors in the predicted SPRs based on conversion table values were further investigated. The SPRs of the five mouthpiece materials were predicted from their computed tomography (CT) numbers using a calibrated conversion table. Independently, the SPRs of the materials were measured from the Bragg peak shift of a carbon-ion beam passing through the materials. The errors in the SPRs of the materials were determined as the difference between the predicted and measured values. The measured SPRs (errors) of the Nipoflex 710â„¢ and Bioplastâ„¢ ethylene-vinyl acetate copolymers (EVAs) were 0.997 (0.023) and 0.982 (0.007), respectively. The SPRs of the vinyl silicon impression material, light-curable resin, and bis-acrylic resin were 1.517 (0.134), 1.161 (0.068), and 1.26 (0.101), respectively. Among the five tested materials, the EVAs had the lowest SPR errors, indicating the highest human-tissue equivalency.}, pages = {83--88}, title = {Stopping-power ratio of mouthpiece materials for charged-particle therapy in head and neck cancer.}, volume = {15}, year = {2021} }