Subjective Image Quality of Cone-Beam CT, Developed by NSTDA, Thailand

Sangsom Prapayasatok, Apirum Janhom, Karune Verochana, Phattaranant Mahasantipiya, Jongdee Kambangton, Arnon Charuakkra


Objective: To compare CBCT image quality on visibility of anatomical structures between the CBCT scanner manufactured in Thailand and the commercial Promax 3D® scanner from Finland.

Materials and methods: Three human skulls were radiographed using the DentiScan® (NSTDA, Thailand) and the Promax 3D® (Helsinki, Finland). Five observers reviewed the CBCT images and assessed the image quality on the visibility of twelve anatomical structures related to the dental tasks, on a five-point scale (1 = excellent; 2 = good; 3 = acceptable; 4 = poor; 5 = very poor).  Overall variation in the visibility from all anatomical structures and per structure were analyzed and compared using Wilcoxon signed rank test (p<0.05).

Results: When all anatomical structures were considered in total, the images from the Promax 3D® gave better subjective image quality than those from the DentiScan® (p-value = 0.0000). When each structure was considered, the results showed higher visibility score for images from Promax 3D® in most of the structures. However, it was found that the median scores for the visibility of the structures from the DentiScan® were rated as good to excellent for mental foramen, incisive foramen, cortical bone, trabecular bone, floor of the maxillary sinus, enamel, dentine, and pulp canal; as acceptable for mandibular canal and lingual foramen; and as bad to very bad for periodontal ligament space and lamina dura.

Conclusions: Compared to the commercial Promax 3D®, the DentiScan® gave lesser image quality on the visibility of the human skull and jaws structures.  However, the visibility score were rated as acceptable to excellent for most of the structures for the DentiScan®. The DentiScan®, the CBCT scanner manufactured in Thailand, can be another choice of CBCT machine for general dental tasks, except the tasks that require high image resolution such as the detection of root fracture.

Keywords: CBCT, DentiScan®, Promax 3D®, image quality