Abstract
Purpose: Cone-beam computed tomography (CBCT) has been widely applied in dental and maxillofacial imaging. Several dental CBCT systems have been recently developed in order to improve the performance. This study aimed to evaluate the image quality of our prototype (YMU-DENT-P001) and compare with another commercial CBCT system made in Taipei, Taiwan (system A). Methods: The Micro-CT-Contrast Scale, Micro-CT Water and Micro-CT HA phantoms were utilized to evaluate the contrast to noise ratio (CNR), signal to noise ratio (SNR), uniformity, distortion, and the linear relation between image intensity and calcium hydroxyapatite concentrations. Another customized thin-wire phantom was used to evaluate the FWHM spatial resolution. These phantoms were scanned by the two CBCT systems using the same exposure protocol. Acquired data were evaluated using the image analysis platform designed by our lab, which followed ISO standard. Results: The SNR of our prototype YMU-DENT-P001 is nearly five times higher (prototype: 159.85 ± 3.88; A: 35.42 ± 0.61; p<0.05) while CNR is three times higher than system A (prototype: 329.39 ± 5.55; A: 100.29 ± 2.31; p < 0.05). The spatial resolutions recorded are 0.2446 mm in the prototype DENT and 0.5179 mm in the commercial system A. Image produced by the prototype is also better in terms of distortion level (0.03 mm in prototype, compared to 0.294 mm in A, p < 0.05). The linear relationship between bone mineral density (BMD) and image intensity of both systems were similarly performed.Conclusion: Within the limitation of this study, our prototype DENT-P001 has potential to produce better image quality than system A in terms of spatial resolution, SNR, CNR, uniformity, and distortion.
An in-house software program for quantitative image quality evaluation of linac cone-beam CT system