Are Dental X-Rays Safe? Radiation, Risks and What You Need to Know

It is a question many patients ask: "Is it really necessary to have an X-ray?" and "How safe are they?" The short answer is that dental X-rays involve an extremely small amount of radiation. Far less than many everyday exposures you may not even think about. Here is a detailed look at what the science actually says.

How Much Radiation Are We Talking About?

Radiation doses are measured in millisieverts (mSv). To put dental X-rays into perspective, here is how they compare to other common exposures:

Due for a check-up and X-rays? Search for dentists with availability near you.

Modern Digital X-Rays: Even Lower Doses

If your practice still used old-fashioned film X-rays, the doses above would be somewhat higher. The good news is that the vast majority of UK dental practices now use digital X-ray sensors, which require up to 80% less radiation than traditional film to produce a clear image.

Digital X-rays also offer additional advantages: the images appear instantly on screen (no waiting for film to develop), they can be enhanced and zoomed for better diagnosis, and they are easier to store and share securely. If your practice has not yet gone digital, it may be worth asking about it at your next visit.

Why Does the Dentist Leave the Room?

This is the question that makes many patients nervous: "If it is so safe, why do you leave the room?" The answer is straightforward and has nothing to do with the risk to you as a patient.

A patient might have one or two X-rays at a visit, perhaps a few times a year. A busy dentist, however, may take dozens of X-rays every single day, five days a week, for an entire career spanning 30 or 40 years. While the dose from each individual X-ray is negligible, the cumulative exposure from standing next to hundreds of thousands of X-rays over a career would add up. Leaving the room is a sensible precaution to keep occupational exposure as low as reasonably achievable — a principle known as ALARA.

When Are Dental X-Rays Needed?

Dentists in the UK follow guidelines from the Faculty of General Dental Practice (FGDP) on when to take X-rays. They should only be taken when there is a clinical justification — your dentist should not be X-raying you routinely at every visit "just because."

Common reasons for dental X-rays include:

• Detecting decay between teeth that cannot be seen during a visual examination
• Assessing bone levels around teeth (important for gum disease diagnosis)
• Checking the health of tooth roots and surrounding bone
• Planning treatment such as extractions, implants, or orthodontics
• Monitoring developing teeth in children and adolescents
• Investigating unexplained pain or swelling

The recommended frequency depends on your risk level. Low-risk adults may only need bitewing X-rays every 12-24 months. Higher-risk patients — those with active decay, gum disease, or a history of frequent dental problems — may need them every 6-12 months.

Pregnancy and Dental X-Rays

This is understandably a common concern. The evidence shows that dental X-rays are considered safe during pregnancy — the radiation dose is extremely low and the beam is directed at your mouth, well away from the developing baby. A lead apron provides an additional layer of protection as standard.

That said, most dentists in the UK prefer to defer routine X-rays until after delivery as a precautionary measure. If you have a dental emergency during pregnancy — such as an abscess or severe infection — X-rays may be clinically necessary, and the small risk of radiation is far outweighed by the risk of leaving an infection untreated. For more on dental care during pregnancy, see our guide on pregnancy and dental problems.

Children and Dental X-Rays

Children are more sensitive to radiation than adults because their cells are dividing more rapidly. However, the doses from dental X-rays are so low that the risk remains negligible. X-rays can be particularly important in children to monitor the development of adult teeth, check for decay in areas that are difficult to examine visually, and plan orthodontic treatment.

Your dentist will only take X-rays of your child when there is a specific clinical reason. The FGDP guidelines recommend that a child's first dental X-rays should be based on individual risk assessment rather than a fixed age. If your child has not yet visited a dentist, see our guide on preparing for their first visit.

Your Right to Refuse

You have every right to decline a dental X-ray. However, it is worth understanding that doing so may limit your dentist's ability to diagnose certain conditions — particularly decay between teeth, which is virtually impossible to detect visually in its early stages. Without X-rays, problems may only become apparent once they are significantly larger and require more complex (and more expensive) treatment.

If you have concerns about X-rays, talk to your dentist. They can explain exactly why they are recommending one and help you make an informed decision. A good dentist will never pressure you but will ensure you understand the implications of declining.