A study on backscatter radiation from dental alloys and a protective device during radiotherapy using a three-dimensional dose distribution analysis system

2016 Fiscal Year Final Research Report

• Project/Area Number: 24592830
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Pathobiological dentistry/Dental radiology
• Research Institution: Niigata University
• Principal Investigator: KATSURA Kouji 新潟大学, 医歯学総合病院, 講師 (30283021)
• Research Collaborator: KIMURA Syuhei ; UTSUNOMIYA Satoru
• Project Period (FY): 2012-04-01 – 2017-03-31
• Keywords: 放射線治療 / 歯科用合金 / 後方散乱線 / 口腔粘膜炎 / 予防

Outline of Final Research Achievements

A dental alloy (DA) in the radiation field can cause severe oral mucositis and uncertain dose distribution due to the scattering and absorption of radiation. A spacer is thought to increase the accuracy and safety of radiotherapy. But, the effects of them on dose distribution have not been clarified. This study was conducted to identify the change of dose distribution caused by backscatter radiation from DAs and the optimal material and thicknesses of a spacer. This study showed that the dose enhancement caused by back and lateral scatter radiation from DA disappears at distances >= 6 mm and >= 3 mm, respectively. These dose enhancements strongly depended on both an atomic number and a physical density of DA, and the estimated equation was 0.077√atomic number + 0.79. Additionally, the optimal material and thickness of spacer should have a lower atomic number and physical density and the thickness of >= 6 mm each to prevent severe mucositis caused by backscatter radiation from DAs.

Free Research Field

歯科放射線学