Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan, ROC.
School of Dentistry, College of Dentistry, China Medical University, Taichung, Taiwan, ROC.
PLoS One. 2018 Dec 26;13(12):e0209698. doi: 10.1371/journal.pone.0209698. eCollection 2018.
This study used available or purchased equipment and an image reconstruction system developed by the college of dentistry to establish a basic self-assembled micro-computed tomography (micro-CT) system. Such a system would be suitable for teaching dental radiology to dental students. Specifically, it could help students to understand the principles governing dental cone-beam computed tomography (CBCT) and provide graduate students with a system for scanning small samples (e.g., individual teeth) during the early stages of research. The self-assembled micro-CT system was constructed using a portable dental X-ray tube, an intraoral digital X-ray detector, a high-precision rotation stage, related bracket accessories, and a notebook computer. Reconstructed images and three-dimensional models of the maxillary right third molar were produced using the self-assembled micro-CT system and an advanced commercially available micro-CT system (Skyscan 2211). Subsequently, the reconstructed images and 3D models produced using the two systems were compared by two senior dentists to determine whether considerable visual differences could be observed. Finally, the signal-to-noise ratio (SNR) was used for quantitative analysis and to compare the systems. Although the self-assembled micro-CT system produced image boundaries that were not as sharp as those of Skyscan 2211, the images were nonetheless remarkably similar. In addition, the two micro-CT systems produced 3D models that were almost identical in appearance and root canal shape. Quantitative analysis revealed that Skyscan 2211 had produced a SNR that was superior to that of the self-assembled micro-CT system, with the difference ranging from 36.77% to 136.22%; enamel, which has a higher density, exhibited lower SNR differences, whereas dentin, which has a lower density, exhibited higher SNR differences. The self-assembled micro-CT system with a resolution of 36 μm was created using a portable dental X-ray tube and an intraoral digital X-ray detector. Although the scanning time was relatively long (~30 min to scan images of a tooth), the images were adequate in the preliminary stage of experiments. More importantly, students were afforded the opportunity to observe the process of assembling and disassembling each component of a micro-CT scanner and thereby achieve a more comprehensive understanding of the principles governing micro-CT and dental CBCT.
本研究利用牙科学院现有的或购买的设备和图像重建系统，建立了一个基本的自行组装的微计算机断层扫描（micro-CT）系统。这样的系统将适合向牙科学学生教授牙科放射学。具体来说，它可以帮助学生理解牙科锥形束计算机断层扫描（CBCT）的原理，并为研究生提供一个用于在研究早期扫描小样本（例如单个牙齿）的系统。自行组装的 micro-CT 系统使用便携式牙科 X 射线管、口腔内数字 X 射线探测器、高精度旋转台、相关支架配件和笔记本电脑构建。使用自行组装的 micro-CT 系统和先进的商用 micro-CT 系统（Skyscan 2211）生成上颌右侧第三磨牙的重建图像和三维模型。然后，由两位资深牙医比较两个系统生成的重建图像和 3D 模型，以确定是否可以观察到明显的视觉差异。最后，使用信噪比（SNR）进行定量分析并比较系统。虽然自行组装的 micro-CT 系统生成的图像边界不如 Skyscan 2211 锐利，但图像非常相似。此外，两个 micro-CT 系统生成的 3D 模型在外观和根管形状上几乎相同。定量分析显示，Skyscan 2211 产生的 SNR 优于自行组装的 micro-CT 系统，差异范围为 36.77%至 136.22%；密度较高的釉质表现出较低的 SNR 差异，而密度较低的牙本质表现出较高的 SNR 差异。分辨率为 36μm 的自行组装 micro-CT 系统使用便携式牙科 X 射线管和口腔内数字 X 射线探测器创建。虽然扫描时间相对较长（扫描一颗牙齿的图像约 30 分钟），但在实验的初步阶段，图像足够了。更重要的是，学生有机会观察到微 CT 扫描仪每个组件的组装和拆卸过程，从而更全面地了解微 CT 和牙科 CBCT 的原理。
