Ultra-low dose CBCT Scanning
X-rays are a form of energy – like light and radio waves. X-rays are also called radiation. Unlike light waves, x-rays have enough energy to pass through your body. As the radiation moves through your body, it passes through bones, tissues, and organs differently. This allows us to create images of them.
X-rays allow us to see the structures in very fine detail.
Cone beam computed tomography (CBCT)
Cone beam computed tomography (CBCT) is a medical imaging technique consisting of X-ray computed tomography where the X-rays are divergent, forming a cone.
During dental/orthodontic imaging, the CBCT scanner rotates around the patient’s head, obtaining up to nearly 600 distinct images.
Measuring radiation dosage
When radiation passes through the body, some of it is absorbed. The x-rays that are not absorbed are used to create the image. The amount the patient absorbs contributes to the patient’s radiation dose. Radiation that passes through the body does not contribute to this dose. The scientific unit of measurement for whole body radiation dose, called “effective dose,” is the millisievert (mSv).
Doctors use “effective dose” when they talk about the risk of radiation to the entire body. Effective dose considers how sensitive different tissues are to radiation. If you have an x-ray exam that includes tissues or organs that are more sensitive to radiation, your effective dose will be higher.
Effective dose allows your doctor to evaluate your risk and compare it to common, everyday sources of exposure, such as natural background radiation.
Naturally occurring background radiation
We are exposed to natural sources of radiation all the time. According to recent estimates, the average person receives an effective dose of about 3 mSv per year from natural radiation, which includes cosmic radiation from outer space. These natural “background doses” vary according to where you live.
People living at high altitudes receive about 1.5 mSv more per year than those living near sea level. A coast-to-coast round-trip airline flight is about 0.03 mSv due to exposure to cosmic rays. The largest source of background radiation comes from radon gas in our homes (about 2 mSv per year). Like other sources of background radiation, the amount of radon exposure varies widely depending on where you live.
To put it simply, the amount of radiation from one adult chest x-ray (0.1 mSv) is about the same as 10 days of natural background radiation that we are all exposed to as part of our daily living.
Effective radiation dose in adults
Here is an approximate comparison of background radiation and effective dental radiation dose in adults. These values can vary, depending on the size of the patient and the type of imaging technology being used.
At the Scanning Suite we use an ultra-low dose CBCT scanner.
| Procedure | Approximate Effective Radiation Dose | Comparable to Natural Background Radiation for: |
|---|---|---|
| Dental X-Ray | 0.005 mSv | 1 Day |
| Panoramic X-Ray | 0.025 mSv | 3 Days |
| Cone Beam CT | 0.18 mSv | 22 Days |
| Procedure | Approximate Effective Radiation Dose | Comparable to Natural Background Radiation for: |
|---|---|---|
| Dental X-Ray | 0.005 mSv | 1 Day |
| Panoramic X-Ray | 0.025 mSv | 3 Days |
| Cone Beam CT | 0.18 mSv | 22 Days |