Routine dental visits frequently include X-rays to help your dentist accurately assess your dental health. But even though they are a valuable diagnostic tool with minimal radiation exposure, you don’t want more X-rays taken than necessary. So the question is: How often and when are dental X-rays needed?
Common Dental X-rays
Even with the best of eyes, dentists cannot see between or inside your teeth, nor can they see the roots of your teeth or the bone that surrounds them. Bitewing X-rays, commonly taken during routine dental visits, can show cavities starting to develop between your teeth, as well as bone loss due to gum (periodontal) disease, while periapical X-rays are used to diagnose an abscess or a cyst, and to disclose changes to the roots of the teeth and surrounding bone. And if you ever need your wisdom teeth removed, your dentist may take a panoramic X-ray. This type of X-ray reveals your entire mouth in one image, allowing your dentist to pinpoint the exact location of impacted teeth, tumors or problems with your temporomandibular joint (jaw joint or TMJ).
How Often Are Dental X-rays Needed?
The frequency of needing dental X-rays depends on your dental health status. To guide dentists and limit the amount of radiation to which patients are exposed, the American Dental Association (ADA) says in their 2012 recommendations that dentists should always perform a clinical examination and evaluate a person’s oral and medical history before taking any X-rays, and that the guidelines are subject to the treating dentist’s clinical judgment—in short, determining the need for X-rays before taking them.
If you have a history of extensive decay or periodontal problems, for example, your dentist may suggest taking X-rays more often than someone who doesn’t. And because of their developing teeth and jaws, children may need X-rays more often than adults. Paul Manos, DDS, Dental Director for United Concordia Dental in California, adds: “The types of X-rays to take, as well as how often and how many, should be based on the individual clinical needs of the patient, as determined by the treating dentist. One size does not fit all when it comes to dental X-rays.”
The ADA recommendation for a posterior bitewing exam for an adult with decay present and an increased risk for cavities is every six to 12 months, whereas someone with no decay or increased risk may be able to go as long as two to three years between having X-rays taken. The rationale behind longer intervals is that tooth decay progresses slowly through enamel, and even with the longer time between bitewings, any decay would be detected before it reaches the softer dentin portion of the tooth. According to Dr. Manos, “Even though the frequency of the need for X-rays on certain patients may be much lower, these patients should still see their dentists on a regular basis for routine oral evaluations (check-ups), usually no less frequently than once every 12 months.”
What Is the Risk?
Whenever an X-ray is taken, you are exposed to some level of radiation. And because radiation has been linked to some forms of cancer, especially in children, you don’t want to be exposed any more than necessary. But with today’s technology, dental X-rays emit only a very low level of radiation. In fact, the amount of radiation from two bitewing X-rays or one panoramic X-ray is equal to the amount of background radiation you are naturally exposed to in one day. However, even though radiation exposure from dental X-rays is low, radiation accumulates in the body from multiple sources over time and never dissipates.
The ADA recommends that dentists follow the ALARA principle (as low as reasonably achievable) whenever exposing their patients to radiation. So, besides not taking any unnecessary X-rays, your dentist’s X-ray equipment should emit the lowest levels of radiation possible. And to further guard you against unnecessary radiation, your dentist should protect your abdominal area and thyroid with an appropriately shielded covering. Always tell your dentist if you are pregnant, although the ADA says that there is no reason to delay required X-rays as long as the appropriately shielded apron and collar are used on the patient.
Keeping X-rays to a Minimum
Here are a few ways you can save yourself the cost and radiation exposure of potentially unnecessary dental X-rays.
- Maintain good dental health with a diligent routine of brushing and flossing, and see your dentist regularly for checkups.
- When changing dentists, take your most recent X-rays with you.
- Discuss concerns about the frequency of X-rays with your dentist. He or she may have suggestions to help you go longer between exposures without compromising your dental health.
So, to answer the question, are dental X-rays needed? The answer is yes. They are sometimes necessary because, without them, small unidentified problems can become bigger and more difficult to treat. But what you don’t want is to have X-rays taken without a valid clinical reason.