Ex vivoevaluation of new 2D and 3D dental radiographic technology for detecting caries

Abstract

Objectives: Proximal dental caries remains a prevalent disease with only modest detection rates by current diagnostic systems. Many new systems are available without controlled validation of diagnostic efficacy. The objective of this study was to evaluate the diagnostic efficacy of three potentially promising new imaging systems. Methods: This study evaluated the caries detection efficacy of Schick 33 (Sirona Dental, Salzburg, Austria) intraoral digital detector images employing an advanced sharpening filter, Planmeca ProMax ® (Planmeca Inc., Helsinki, Finland) extraoral "panoramic bitewing" images and Sirona Orthophos XG3D (Sirona Dental) CBCT images with advanced artefact reduction. Conventional photostimulable phosphor images served as the control modality. An ex vivo study design using extracted human teeth, ten expert observers and micro-CT ground truth was employed. Results: Receiver operating characteristic analysis indicated similar diagnostic efficacy of all systems (ANOVA p . 0.05). The sensitivity of the Schick 33 images (0.48) was significantly lower than the other modalities (0.53-0.62). The specificity of the Planmeca images (0.86) was significantly lower than Schick 33 (0.96) and XG3D (0.97). The XG3D showed significantly better cavitation detection sensitivity (0.62) than the other modalities (0.48-0.57). Conclusions:The Schick 33 images demonstrated reduced caries sensitivity, whereas the Planmeca panoramic bitewing images demonstrated reduced specificity. XG3D with artefact reduction demonstrated elevated sensitivity and specificity for caries detection, improved depth accuracy and substantially improved cavitation detection. Care must be taken to recognize potential false-positive caries lesions with Planmeca panoramic bitewing images. Use of CBCT for caries detection must be carefully balanced with the presence of metal artefacts, time commitment, financial cost and radiation dose.

Are metal artefact reduction algorithms effective to correct cone beam CT artefacts arising from the exomass?

“…Moreover, it is well known that CBCT image is severely influenced by artefacts, which compromise specific diagnostic tasks. [24][25][26] Thus, in an endeavour to overcome some artefact-related limitations, MAR algorithms have been developed and, given its relatively recent advent, scientific studies have focused on the effectiveness of MAR when high-density objects of high atomic number are observed inside the FOV.…”

Metallic materials in the exomass impair cone beam CT voxel values

“…[10][11][12] The variability of the voxel values in CBCT contributes to generate artefacts in the reconstructed images, [13][14][15] which may reduce diagnostic accuracy. [16][17][18] It is well-known that an important source of image artefact is the presence of metal objects in the field of view (FOV). 16,17 When the FOV encompasses just a portion of an object which is entirely located in the path of the X-rays (between the focal area and the image detector), this is known as local tomography.…”

3D imaging of proximal caries in posterior teeth using optical coherence tomography

“…The rate of detection of proximal caries using standard 2D bitewing radiographs is about 60% 12 . On the other hand, 3D cone-beam computed tomography (CBCT) affords better results for cavitated proximal lesions with an approximately 30% increase in detection rate 49 . However, CBCT is not considered suitable for use in routine clinical practice because of the high effective radiation doses of 11-77 μSv, depending on the field of view, exposure parameters, and region examined 50 .…”