Are you concerned about the amount of radiation you get from dental x-rays? You can take that off your list of worries.
Dental x-rays are one of the lowest radiation studies you can have done. A routine exam, with four bitewings, causes the body to absorb about 0.005 mSv (millisievert) of radiation, which is less than one day of natural background radiation in the environment. This is also about the same amount of radiation you would receive from a one-to-two-hour airplane flight.
A panoramic x-ray provides more radiation, but only about 0.007 mSV.
One millisiervert is the average accumulated background radiation dose to an individual for one year, exclusive of radon, in the United States.
When do you need x-rays?
Dental x-rays help your dentist see damage and disease not visible to the naked eye.
How often you need them depends on your oral health, your age, and your disease risk. Children need x-rays more often than adults because their teeth and jaws are still developing, and their teeth are more prone to tooth decay.
Your dentist will review your history, examine your mouth and then decide whether or not to do x-rays.
X-rays for new patients
If you are a new patient, the dentist may recommend x-rays to determine the status of your oral health and have a baseline for the future. A new set of x-rays may be needed to find any new cavities, determine the status of your gum health or evaluate the growth and development of your teeth.
If your previous dentist has x-rays of your mouth, your new dentist may ask you have copies of them forwarded.
While the dentist or oral surgeon may put a lead apron or thyroid collar on you, this is only out of an abundance of precaution. The radiation from dental x-rays is not thought to increase the risk of cancer.
Today’s x-rays emit less radiation than in the past
Dental patients are exposed to lower levels of radiation today than in the past. Digital technologies, more precise radiation beams, and shields placed over patients’ chests and thyroids make getting an x-ray safer today than ever before.
Even for pregnant women, dental x-rays are safe. Dental X-rays do not need to be delayed if you are trying to become pregnant or are breastfeeding.
To protect children, The American Dental Association has joined with more than 80 other health care organizations to promote Image Gently, an initiative to “child size” x-rays of children in medicine and dentistry.
Providers are urged to:
- select X-rays for individual needs, not as a routine;
- use the fastest image receptor available;
- use cone-beam CT (CBCT) only when necessary;
- collimate the beam to the area of interest;
- “child-size” the exposure time
A leaded thyroid collar is recommended for women of childbearing age, pregnant women and children.
Risks and benefits
Some studies have shown a link between dental x-rays and thyroid cancer and certain forms of brain cancer, but these studies have been questioned, because they rely on patients’ recollection of how many x-rays they’ve had, not actual data. People tend to guess more x-rays than they have actually had.
When considering a dental x-ray, weigh the potential benefits of early and accurate diagnosis of disease against the very minimal risks of cancer from an accumulation of radiation. The risk of long-term complications from an untreated dental disease is much higher that the risk of cancer from an x-ray.