CBCT and Radiation FAQs

People often have questions about CBCT scans. Below are some questions that we are frequently asked. If you have other questions, please ask one of our staff and they would be glad to explain things to you.

What is a CBCT?

CBCT stands for Cone Beam Computed Tomography. CBCT, also known as a CT or CAT scan, sends x-rays through the patient’s body to form a picture of the inside of the body.

How is CBCT different than an x-ray film?

To make an x-ray film, an x-ray machine sends x-rays through a patient toward a film creating a “shadow” on the film. With CBCT, an x-ray machine circles around the patient, sending x-rays as it goes around. Using a computer, pictures are created that look like many “slices” of the body. These pictures tell more about the inside of the body than x-ray film.

How much radiation is used?

Very little. All of us receive small amounts of radiation all the time—mainly from the sun and the soil. Scientists call this background radiation. To put it into perspective, we can compare the amount of radiation used in dental CBCT and x-ray films to the amount of background radiation we receive every day.


  • Dental x-ray
  • 3 hour airline flight
  • Dental CBCT scan
  • Chest x-ray
  • Head CT
  • Abdominal CT
  • Chest CT
  • Upper GI x-ray
  • Lower GI x-ray
  • Abdominal and Pelvis CT


  • 1 day or less
  • 1 day
  • 1-4 days
  • 10 days
  • 4 months
  • 1.5 years
  • 2 years
  • 2 years
  • 3 years
  • 3 years

Adapted from: http://www.radiologyinfo.org/en/info.cfm?pg=safety-xray


According to the FDA, when used appropriately, the benefits of a CBCT scan far exceed the risks. X-ray imaging, including dental CBCT, provides a fast, non-invasive way of answering a number of clinical questions. Dental CBCT images provide detailed, three-dimensional (3-D) information, rather than the two-dimensional (2-D) information provided by a conventional X-ray image.CBCT scans can provide detailed information to diagnose, plan treatment for, and evaluate many conditions in adults and children. Additionally, the detailed images provided by CBCT scans may eliminate the need for exploratory surgery. (This is according to the FDA which regulates the safety and effectiveness and radiation control of all X-ray imaging devices, including CT, in the US.)

American Association of Physicists in Medicine:  In their 2018 position statement, the American Association of Physicists in Medicine state: “…epidemiological evidence supporting increased cancer incidence or mortality from radiation doses below 100 mSv is inconclusive…Given the lack of scientific consensus about potential risks from low doses of radiation, predictions of hypothetical cancer incidence and mortality from the use of diagnostic imaging are highly speculative. The AAPM, and other radiation protection organizations, specifically discourages these predictions of hypothetical harm…” https://www.aapm.org/org/policies/details.asp?type=PP&id=439 And a dose of 100 millisieverts is hundreds of times more than our small field of view dental CBCT (0.015 to 0.032 millisieverts).