Research contributing to the construction of a radiation protection system for portable intraoral x-ray devices

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K19319
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 57080:Social dentistry-related
• Research Institution: Meikai University
• Principal Investigator: Otaka Yusei 明海大学, 歯学部, 講師 (60711067)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 携帯型口内法X線撮影装置 / 放射線防護 / 放射線防護用品 / 歯科的個人識別 / 訪問診療 / 臥位用パノラマ撮影装置

Outline of Final Research Achievements

The attenuation rate of protection-related products was almost on the attenuation curve of lead. This result was considered to be due to the fact that most protection-related products have an attenuation rate close to the nominal lead equivalent. The effect of reducing the radiation dose to the operator by the rectangular diaphragm alone was about 1/3, and the effect of reducing the radiation dose to the operator when the receiver holder was used in combination with the rectangular diaphragm was about 1/5 to 1/8. The backscatter X-ray attenuation effect when the radiation protection shield and the holding device were used together was about 1/13.It was found that wood and PMMA showed high scattering doses, soil, concrete and rubber plates showed moderate values, and stainless steel plates showed very low values.
In the recumbent X-ray device, it was considered that the highest scattering dose was obtained at the measurement point located ± 30 ° from directly below the phantom.

Free Research Field

歯科放射線学

Academic Significance and Societal Importance of the Research Achievements

放射線から身体を守る鉛エプロンや鉛手袋等の防護関連用品の放射線を減弱する効果は、ほぼ公称値通りの結果であり、品質は保証されていた。歯科的身元確認業務や歯科訪問診療に使用される携帯型X線装置において、照射するX線を絞る装置を装着することにより使用者の被曝線量は約1/5～1/8に減弱され、効果的であることがわかった。さらに、装置前方に円形の放射線を減弱するシールドを併用した場合は、被曝線量を約1/13に減弱することがわかった。
御遺体を安置する材質によってX線装置の使用者の被曝線量は変化し、木材では高い線量を示し、金属では非常に低い値を示すことが解った。