Radiation Dose

The effective dose of any imaging modality is a number that considers the absorbed energy within the tissue, the radiation-weighting factor and the tissue-weighting factor according to the International Commission on Radiation Protection (ICRP) 2007. The effective dose of CBCT is generally low although not constant. It depends on multiple factors, including exposure parameters (kV and mA), filtration, field of view (FOV) and number of projections.

The literature describes a wide range of radiation dose from different CBCTs. The range of effective dose according to SEDENTEXCT ranged from 11–674µSv for dento-alveolar dental CBCT unit type and from 30–1073µSv for a cranio-facial dental CBCT unit type. The range of effective dose according to Ludlow et al ranged from 68–1,073µSv for a large-volume CBCT scan, from 69–560µSv for a medium-volume scan, and from 189– 652µSv for a small-volume CBCT scan.

It is important therefore to know the radiation dose from the imaging modality you are requesting. Here at The Cone Beam CT Centre, we always display the dose from the examination on the images that are sent back to you. We also carry out a regular audit on radiation dose to ensure that we continue providing high quality images with the lowest possible dose to your patient.

References Ludlow JB, Ivanovic M. Comparative dosimetry of dental CBCT devices and 64-slice CT for oral and maxillofacial radiology. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2008; 106: 106–114. Guidelines on CBCT for Dental and Maxillofacial Radiology.