An investigation into dose optimisation for imaging root canal anatomy using cone beam CT

Objectives: To identify a dose as low as diagnostically acceptable and a threshold level of image quality for cone beam CT (CBCT) imaging root canals, using maxillary first molar (M1M) second mesiobuccal (MB2) canals of varying complexity for two CBCT scanners. Methods: Dose–area product (DAP) and contrast-to-noise ratio (CNR) were measured for two scanners at a range of exposure parameters. Subjective-image-quality assessment at the same exposures was performed for three M1Ms of varying MB2 complexity, positioned in an anthropomorphic phantom. Nine raters (three endodontists, three dental radiologists and three junior staff) assessed canal visibility, using a 5-point confidence scale rating. Results: Identification of simple-moderate MB2 canal complexity was achieved at a range of protocols, with DAP values of ≥209.3 and ≥203.2 mGy cm² and CNRs of 3 and 7.6 for Promax®3D and Accuitomo-F170® respectively. For complex canal anatomy, target subjective image quality was not achieved, even at the highest DAP values for both scanners. Junior staff classified significantly more images as undiagnostic compared with senior staff (p = 0.043). Conclusions: In this first study to address optimisation of CBCT imaging of root canal anatomy, a similar threshold dose for both scanners was identified for M1Ms with simple-moderate MB2 canal complexity. Increasing dose to enhance visualisation of more complex canal anatomy was ineffective. Selection of standard protocols (while avoiding lower kV/mA protocols) instead of high-resolution scans was a practical means of reducing patient dose. CNR is not a transferable measure of image quality.

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Imaging of root canal fillings: a comparison of subjective image quality between limited cone-beam CT, storage phosphor and film radiography

International Endodontic Journal ◽

10.1111/j.1365-2591.2007.01204.x ◽

2007 ◽

Vol 40 (3) ◽

pp. 179-185 ◽

Cited By ~ 46

Author(s):

E. Soğur ◽

B. G. Baksı ◽

H.-G. Gröndahl

Keyword(s):

Image Quality ◽

Root Canal ◽

Cone Beam Ct ◽

Cone Beam ◽

Subjective Image Quality ◽

Storage Phosphor

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A 3D printed phantom for Image Quality Assessment in Cone-beam CT

Physica Medica ◽

10.1016/j.ejmp.2018.06.031 ◽

2018 ◽

Vol 52 ◽

pp. 170

Author(s):

James O’Halloran ◽

Paddy Gilligan ◽

Sinead Cleary ◽

Susan Maguire ◽

Gerald O’Connor ◽

...

Keyword(s):

Image Quality ◽

Quality Assessment ◽

Image Quality Assessment ◽

Cone Beam Ct ◽

Cone Beam ◽

3D Printed

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Subjective Image Quality Assessment at the Threshold Level

TENCON 2005 - 2005 IEEE Region 10 Conference ◽

10.1109/tencon.2005.300872 ◽

2005 ◽

Author(s):

C. White ◽

R. Martin ◽

D. Wu ◽

C. Tan ◽

D. Tan ◽

...

Keyword(s):

Image Quality ◽

Quality Assessment ◽

Image Quality Assessment ◽

Threshold Level ◽

Subjective Image Quality

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Relationship between CNR and visibility of anatomical structures of cone-beam computed tomography images under different exposure parameters

Dentomaxillofacial Radiology ◽

10.1259/dmfr.20190336 ◽

2020 ◽

Vol 49 (5) ◽

pp. 20190336

Author(s):

Miss Fei Wang ◽

Xiaoyan Xie ◽

Gang Li ◽

Zuyan Zhang

Keyword(s):

Image Quality ◽

Change Point ◽

Cone Beam Ct ◽

Cone Beam ◽

Physical Factors ◽

Anatomical Structures ◽

Subjective Image Quality ◽

Computed Tomography Images ◽

Tissue Equivalent ◽

Imagej Software

Objectives: The purpose of this study was to investigate the image quality of cone beam CT (CBCT) under different exposure parameters and the relationship between contrast-to-noise and visibility of eight anatomical structures. Methods: CBCT images for the evaluation of subjective image quality were acquired on an anthropopathic phantom containing a human skeleton embedded in soft tissue equivalent materials using 25 exposure protocols. Visibility of eight anatomical structures was evaluated by five independent observers. Using the SEDENTEXCT IQ Image Quality phantom, the contrast-to-noise ratio (CNR) was calculated by ImageJ software. Results: A reduction on the visibility of anatomical structures was seen under lower exposure parameters. However, for 84% of the protocols, visibility of anatomical structures remained acceptable even under some lower parameter settings. As CNR increased, the visibility of anatomical structures also increased correspondingly. A change point could be found in the CNR interval 29.42–36.51 after which the visibility of anatomical structures no longer increases with the increase of CNR. Conclusions: Although CNR decrease under a lower exposure parameter, the image quality often remained acceptable at exposure levels below the manufacture’s recommended settings. It is possible to standardize subjective image quality by physical factors. Currently, it is not possible to predetermine a change point CNR value due to different CBCT machine and variation of diagnostic tasks.

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Interrelationships in the Variability of Root Canal Anatomy among the Permanent Teeth: A Full-Mouth Approach by Cone-Beam CT

PLoS ONE ◽

10.1371/journal.pone.0165329 ◽

2016 ◽

Vol 11 (10) ◽

pp. e0165329 ◽

Cited By ~ 17

Author(s):

Paul Monsarrat ◽

Bertrand Arcaute ◽

Ove A. Peters ◽

Elisabeth Maury ◽

Norbert Telmon ◽

...

Keyword(s):

Root Canal ◽

Cone Beam Ct ◽

Cone Beam ◽

Permanent Teeth ◽

Root Canal Anatomy

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[P261] Image quality assessment of filtered dual energy cone beam CT for radiotherapy

Physica Medica ◽

10.1016/j.ejmp.2018.06.540 ◽

2018 ◽

Vol 52 ◽

pp. 174-175

Author(s):

Mikkel Skaarup ◽

Jens M. Edmund ◽

Ivan Vogelius

Keyword(s):

Image Quality ◽

Quality Assessment ◽

Image Quality Assessment ◽

Cone Beam Ct ◽

Dual Energy ◽

Cone Beam ◽

Energy Cone

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Occurrence and Morphology of MB2 Canals in Maxillary First Molars in an Indian Subpopulation: A Cone Beam Computed Tomography Study

Journal of Health and Allied Sciences NU ◽

10.1055/s-0041-1736268 ◽

2021 ◽

Author(s):

Aditya Shetty ◽

Raksha Bhat ◽

Bessy Babu ◽

Mithra N. Hegde ◽

Chitharanjan Shetty ◽

...

Keyword(s):

Root Canal ◽

Cone Beam Ct ◽

Descriptive Analysis ◽

Conventional Radiography ◽

Cone Beam ◽

Inclusion Criteria ◽

Type Iv ◽

Maxillary Molars ◽

Root Canal Anatomy ◽

Case Basis

Abstract Introduction Molars have been known to display varied morphologies. Maxillary first molar is the tooth with the largest volume and most complex root and root canal anatomy; also, possibly the most treated and least understood posterior tooth. The present study aimed to investigate the occurrence and morphology of MB2 canals in maxillary first molars in an Indian subpopulation (Dakshina kannada) using cone beam CT (CBCT) imaging. Materials and Methods A total of 330 maxillary molars were placed on “U-” shaped modelling wax template, mimicking the natural arch and digitally scanned, of which 196 scans met the inclusion criteria and were analyzed for unusual root canal anatomy by CBCT. To analyze the occurrence and morphology of the canals, the acquired data was examined by two endodontists and discussed till an agreement was reached. Results The results were subjected to descriptive analysis. The majority of patients 103 (52.6%) teeth showed the presence of MB2 canals. As much as 83.5% of teeth depicted Vertucci's type II morphology, and 16.5% teeth presented with Vertucci's type IV morphology. Conclusion CBCT overcomes the limitations of conventional radiography. However, the decision to use CBCT in the management of endodontic problems must be based on a case-by-case basis and only when sufficient diagnostic information is not obtained from diagnostic tests.

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