In comparison to conventional medical computed tomography (CT), cone-beam CT (CBCT) has become widely used in dental and maxillofacial applications due to its accurate 3D information, high resolution, minimal radiation dose, and affordable machine cost. In this study, we investigated the image quality and radiation doses of dental CBCT and X-ray machines developed in Thailand. Our in-house reconstruction algorithm including artifact reduction was based on GPU calculations of filtered backprojection and was significantly faster than a CPU-based algorithm. The image quality aspects for CBCT were evaluated in terms of high contrast resolution, gray value uniformity, noise, and geometric accuracy, while image quality assessment for 2D images included high contrast resolution, low contrast levels, and distortion rate. Radiation doses were measured and calculated for the dose-area product (DAP). The technical image quality and radiation dose assessment was compared with those of other commercial extraoral imaging machines. The findings demonstrate that, when compared to other units, the proposed 2D and 3D extraoral imaging systems yielded comparable technical image quality and radiation doses. Based on these results, the Thai-made 2D and 3D extraoral imaging machines appear suitable for further clinical evaluation.
Thongvigitmanee et al. (2026) studied this question.