Digital radiography requires less radiation because of the manner in which the digital plates are exposed. To generalize, a traditional dental film needs greater radiation to “expose” it than does a digital sensor. Stated another way, digital sensors need less ionizing radiation to “expose” it than do traditional films.
There are many ways to measure radiation exposure, but the most common way is to use the unit called a Sievert (Sv). A Sievert is a measure of the equivalent dose which is basically the amount of radiation that is absorbed by human tissue along with the potential tissue damage that could occur. Most equivalent doses measured in healthcare settings use the milliSievert or mSv.
To appreciate digital dental radiography against other sources of radiation, consider this table:
| Source | Equivalent Dose (mSv) |
| Digital Dental Bitewing X-Ray | .005 |
| Traditional (D speed) Dental Bitewing X-Ray | .017 |
| Digital Panoramic Radiograph | .020 |
| Traditional Film Chest X-Ray | .100 |
| Traditional Film Mammogram | .700 |
| Traditional Film Abdominal CT Scan | 8.00 |
| Flight from London to Los Angeles | .080 |
The following sources were used to compile this radiation data:
John B. Ludlow, DDS, MS, FDS RCSEd, Professor, Department of Diagnostic Sciences, University of North Carolina School of Dentistry, Chapel Hill, North Carolina, USA, April 25, 2011.
Optimisation of radiation protection for pediatric and adult patients in radiography and computed tomography. Geleijns, Jacob. Proceedings of Third European IRPA Congress, June 2010.
European Commission. Radiation Protection 136. European Guidelines on Radiation Protection in Dental Radiology. Luxembourg: Office for Official Publications of the European Communities, 2004.
