İçöz Derya, Gül Osman Vefa
Faculty of Dentistry, Department of Oral and Maxillofacial Radiology, Selcuk University, Konya 42130, Turkey.
Faculty of Medicine, Department of Radiation Oncology, Selcuk University, Konya 42130, Turkey.
Dentomaxillofac Radiol. 2025 Mar 1;54(3):231-238. doi: 10.1093/dmfr/twaf007.
Due to the increasing use of cone-beam CT (CBCT) in dentistry and considering the effects of radiation on radiosensitive organs, the aim of this study was to investigate the effect of shielding on absorbed dose of eyes, thyroid, and breasts in scans conducted with different parameters using 2 different fields of view (FOV).
Dose measurements were calculated on a tissue-equivalent female phantom by repeating each scanning parameter 3 times and placing at least 2 thermoluminescent dosimeters (TLD) on each organ, with the averages then taken. The same CBCT scans were performed in 2 different FOV with shielding including thyroid collar, radiation safety glasses, and lead apron and without shielding. The differences between them were analysed statistically. Descriptive statistics and the Wilcoxon test were used for data analysis.
The difference between measurements with and without shielding was statistically significant for all scans (P < .001). The dose reduction associated with the use of shielding ranged from 26.81% to 52.95%. The dose related to the FOV has shown a significant increase, ranging from 8.30% to 623.54%, due to both the variation in the area affected by the primary beam on the organs and changes in the amount of radiation.
There are significant differences in the absorbed dose depending on shielding and FOV usage. Therefore, the CBCT imaging protocol should be optimized by the operator, and special attention should be paid to the use of thyroid collars and radiation safety glasses, considering their effects on image quality.
鉴于锥形束计算机断层扫描（CBCT）在牙科领域的使用日益增加，并考虑到辐射对放射敏感器官的影响，本研究旨在调查在使用两种不同视野（FOV）、不同参数进行扫描时，屏蔽对眼睛、甲状腺和乳房吸收剂量的影响。
通过在组织等效女性体模上重复每个扫描参数3次，并在每个器官上放置至少2个热释光剂量计（TLD），然后取平均值来计算剂量测量值。在两种不同的视野下进行相同的CBCT扫描，一种有屏蔽，包括甲状腺防护颈圈、辐射安全眼镜和铅围裙，另一种无屏蔽。对两者之间的差异进行统计学分析。数据分析采用描述性统计和Wilcoxon检验。
所有扫描中，有屏蔽和无屏蔽测量值之间的差异具有统计学意义（P < 0.001）。与使用屏蔽相关的剂量降低范围为26.81%至52.95%。由于器官上受原发射线影响的面积变化和辐射量的改变，与视野相关的剂量显示出显著增加，范围为8.30%至623.54%。
根据屏蔽和视野的使用情况，吸收剂量存在显著差异。因此，操作人员应优化CBCT成像方案，并特别注意甲状腺防护颈圈和辐射安全眼镜的使用，同时考虑它们对图像质量的影响。
