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Title Cone Beam Computed Tomography Is Effective in Acquiring Anatomical Image Equivalence to a Full-Mouth Series with a Similarly Effective Dose
Clinical Question Can a cone beam CT of maxillary and mandibular view be obtained with no more effective dose then a round collimated, high-speed receptor full-mouth series?
Clinical Bottom Line With respect to effective dose, a CBCT volume of the upper and lower jaws is a possible alternative to a full-mouth series when compared to round collimated, high-speed receptor images.
Best Evidence (you may view more info by clicking on the PubMed ID link)
PubMed ID Author / Year Patient Group Study type
(level of evidence)
#1) 23807928Li/20133 articlesNarrative Review
Key resultsThe International Commission on Radiation Protection defines the average effective dose of 18 high-speed films with round collimnation equal to 170.7 µSv. A cone beam CT scan of the dentoalveolar region (medium field of view) has a range between 28 and 560 µSv effective dose. Fifteen of the 17 CBCT devices had below the intraoral image average of 170.7 µSv.
#2) 25224586Ludlow/201420 articlesMeta-Analysis
Key resultsAdult phantom effective doses for fields of view less than 10 cm in height for maxillary volumes, including the mandible, ranged from 22 to 488 µSv for devices set to standard or default exposures.
Evidence Search ("Cone Beam Computed Tomography*"[MeSH term] OR "CBCT"[All Fields]) AND "Radiation Dose"[all fields] AND "Intra-oral"[all fields]
Comments on
The Evidence
When comparing anatomical equivalence of full-mouth series to CBCT images, CBCT settings are limited to default exposures for small fields of view (less than 10 cm in height) including the mandible. It is difficult to generalize CBCT doses with very large exposure ranges, having both substantial variability among devices and variability within the devices' resolution protocols. Effective dose significantly increases with increase in brain coverage. Variability also exists in the method of calculating dose, using conversion coefficients and applying them to dose-area product or dose-height product. There is no standard measurement. The articles only look at effective dose and not at the comparison of relative diagnostic effectiveness. Clinically there is a preference for modalities with higher signal to noise ratios and higher resolution. Standardization is required with strict following of NCRP and ICRP 2007 recommendations. There is a possible conflict of interest in Ludlow 2014, as the author had travel support from a variety of device companies.
Applicability Technology is constantly changing and new products always available. With the advent of CBCT and its almost limitless range of capabilities, many clinicians and practices use or own these new devices. As diverse as its capabilities, equally diverse are the number of brands and ranges of radiation patients can be exposed to. Research shows it is possible for limited-view CBCT volumes to have similarly effective doses and to include areas of interest comparable to full-mouth series with conventional, round collimated, high-speed receptors.
Specialty/Discipline (Oral Medicine/Pathology/Radiology) (General Dentistry)
Keywords cone beam computed tomography, effective dose
ID# 2800
Date of submission: 12/12/2014spacer
E-mail morchat@uthscsa.edu
Author Michael Morchat, DDS
Co-author(s) e-mail
Faculty mentor/Co-author S. Thomas Deahl, II, DMD, PhD
Faculty mentor/Co-author e-mail DEAHL@uthscsa.edu
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