Dental Diagnostic Center, 79098 Freiburg, Germany.
Dentomaxillofac Radiol. 2013;42(7):20120417. doi: 10.1259/dmfr.20120417. Epub 2013 Apr 12.
Evaluation and reduction of dose are important issues. Since cone beam CT (CBCT) has been established now not just in dentistry, the number of acquired examinations continues to rise. Unfortunately, it is very difficult to compare the doses of available devices on the market owing to different exposition parameters, volumes and geometries. The aim of this study was to evaluate the spans of effective doses (EDs) of ten different CBCT devices.
48 thermoluminescent dosemeters were placed in 24 sites in a RANDO(®) head phantom. Protocols with lowest exposition parameters and protocols with highest exposition parameters were performed for each of the ten devices. The ED was calculated from the measured energy doses according to the International Commission on Radiological Protection 2007 recommendations for each protocol and device, and the statistical values were evaluated afterwards.
The calculation of the ED resulted in values between 17.2 µSv and 396 µSv for the ten devices. The mean values for protocols with lowest and highest exposition parameters were 31.6 µSv and 209 µSv, respectively.
It was not the aim of this study to evaluate the image quality depending on different exposition parameters but to define the spans of EDs in which different CBCT devices work. There is a wide span of ED for different CBCT devices depending on the selected exposition parameters, required spatial resolution and many other factors.
评估和降低剂量是非常重要的问题。由于锥形束 CT(CBCT)不仅在牙科领域得到了应用,而且其应用数量还在不断增加。不幸的是,由于不同的曝光参数、体积和几何形状,很难比较市场上可用设备的剂量。本研究旨在评估十种不同 CBCT 设备的有效剂量(ED)范围。
将 48 个热释光剂量计放置在 RANDO(®)头部体模的 24 个部位。对于十种设备中的每一种,都进行了曝光参数最低的协议和曝光参数最高的协议的拍摄。根据国际辐射防护委员会 2007 年的建议,针对每个协议和设备,从测量的能量剂量中计算 ED,并对统计值进行评估。
十种设备的 ED 计算结果在 17.2µSv 到 396µSv 之间。曝光参数最低和最高协议的平均值分别为 31.6µSv 和 209µSv。
本研究的目的不是根据不同的曝光参数评估图像质量,而是确定不同 CBCT 设备的 ED 范围。根据选择的曝光参数、所需的空间分辨率和许多其他因素,不同的 CBCT 设备的 ED 范围差异很大。