With digital x-rays, a patient’s exposure to radiation can be as little as 10 percent of the dose from a traditional film-based x-ray or radiograph, depending on the type of film used. Studies have also shown that dental x-rays have one of the lowest radiation doses of any type of x-ray. Because the exposure is low, the concern is that dentists may treat it as a free pass for numerous retakes, or take a lax attitude towards radiation safety.
Dental practitioners should weigh the benefits of taking x-rays against the risk of exposing a patient to radiation, no matter how small. They should only order x-rays if they can justify that the additional diagnostic information will make a difference to patient care. A dentist who knows the patient’s health history and susceptibility to oral diseases is in the best position to judge whether the exposure is justified by its benefits.
Good x-ray practices
Although x-rays help to diagnose cavities and diseases that are not visible during a dental examination, any level of radiation poses a potential risk, so you will want to keep your exposure as low as possible. Good practices that help reduce exposure include:
- Following the ALARA principle: as low as reasonably achievable.
- Using a digital x-ray system, or a faster-speed x-ray film (E or F-speed).
- Using rectangular collimators whenever feasible.A rectangular collimator reduces the radiation dose by up to fivefold compared with a circular collimator.
- Using protective aprons and thyroid collars when appropriate.
- Limiting the number of images to the minimum required for the necessary diagnostic information.