Digital dental X-rays are considered safe when a dentist expects the image to answer a clinical question an exam alone cannot. Dental X-ray radiation is low: one bitewing is roughly a day of natural background exposure. Because it is still ionizing radiation, safety depends on taking only the images needed.
Key Takeaways
- According to RadiologyInfo, a bitewing or other intraoral dental X-ray delivers about 0.005 mSv, roughly the same as one day of natural background radiation.
- Dental X-rays should be prescribed after clinical assessment when the expected diagnostic benefit outweighs the radiation risk.
- Digital sensors can support dose-reduction practices, but they do not make imaging risk-free or automatically necessary.
- ALARA means using only the images needed, with techniques that limit unnecessary exposure once imaging is justified.
- Tell your dental team about pregnancy, recent imaging elsewhere and any radiation concerns before X-rays are taken.
Dental X-ray radiation: how much is it?
Dental X-ray radiation is the small dose of ionizing radiation your body receives when an X-ray image of the teeth and jaws is taken. Radiation dose is measured in millisieverts (mSv), and it is often compared with the natural background radiation everyone receives from the ground, air and space.
RadiologyInfo, a patient-information site from radiology professional organizations, gives these approximate effective doses:
| Exam | Approximate effective dose | Comparable natural background radiation |
|---|---|---|
| Intraoral X-ray (bitewing or periapical) | 0.005 mSv | About 1 day |
| Panoramic X-ray | 0.025 mSv | About 3 days |
| Dental cone-beam CT (CBCT) | 0.18 mSv | About 22 days |
| Chest X-ray (for comparison) | 0.1 mSv | About 10 days |
These numbers are averages. Actual dose varies with the equipment, settings, the number of images and the size of the patient, and background radiation itself varies by where you live. The figures show that a routine dental X-ray is among the lowest-dose imaging exams, but they are not a reason to take images without a clinical need. The American Dental Association notes that dental imaging makes up less than 1% of the collective dose from medical imaging each year.
Why dentists prescribe X-rays only when useful
A dental X-ray is a diagnostic tool, not a fixed part of every appointment. Dentists use radiographs to evaluate structures that are not fully visible in the mouth, such as areas between teeth, roots, supporting bone and some restorations. The decision should follow a review of your history, symptoms and clinical findings.
The Canadian Dental Association's position on control of X-radiation states that radiographs should be based on a clinical examination and a need for information that could contribute to diagnosis or treatment planning. The association also advises that dentists try to obtain previous radiographs rather than routinely prescribing new ones, and that the frequency of radiological examination is a matter of clinical judgment.
The American Dental Association similarly notes that there is no one-size-fits-all interval for dental X-rays. Timing depends on current oral health, age, disease risk, signs and symptoms. Guidelines developed with the U.S. Food and Drug Administration emphasize professional judgment after history and examination, rather than automatic imaging on a calendar alone.
Situations that may support imaging include new pain, swelling, trauma, suspected decay between teeth, evaluation of existing restorations, periodontal assessment, developmental questions in growing patients, or planning care that depends on information not visible clinically. Absence of symptoms does not always mean imaging is unnecessary, and presence of concern does not always mean every possible view is required. Our article on why dentists take X-rays covers these reasons in more depth.
If you already have recent images from another office, ask whether they can be reviewed before new exposures are made. Reusing adequate records is one practical way to avoid unnecessary repeats.
How digital imaging relates to radiation exposure
Digital dental X-rays typically use an electronic sensor or phosphor plate instead of traditional film. The receptor captures the image and displays it on a computer for review. Our guide to how digital dental X-rays work explains the process step by step. The ADA notes that digital imaging offers reduced radiation exposure compared with film, and its 2024 recommendations call for digital imaging rather than conventional film.
That does not mean digital imaging eliminates radiation, and it does not support unverified marketing claims about exact dose percentages. Exposure still depends on clinical need, the number and type of images, beam collimation, technique factors, equipment maintenance and operator skill. A digital system used without justification can still produce unnecessary exposure; careful selection of images matters as much as the receptor type.
The ADA also describes a risk called "exposure creep". Because a higher exposure can make a digital image look cleaner, settings can drift upward over time without anyone noticing. Good practice means setting exposures for the diagnostic task and checking equipment regularly. The CDA's position similarly calls for quality assurance programs and regular inspection of X-ray equipment.
For an overview of how digital imaging fits into diagnostic care at the practice, see Landmark Dental Care's information on digital dental X-rays.
What ALARA means in a dental visit
ALARA stands for "as low as reasonably achievable." In dentistry, it means that once a radiograph is justified, the dental team should keep exposure as low as practical while still obtaining the diagnostic information required. The CDA position describes the ALARA concept as keeping the dose to the patient as low as reasonably achievable.
According to ADA discussion of radiologic protection principles, ALARA includes justifying exposures in relation to their benefits, keeping necessary exposures as low as reasonably achievable, and keeping doses to patients and personnel well below allowable limits. ADA/FDA patient-selection guidance likewise frames radiographs as tools the dentist orders after weighing benefit against cumulative radiation risk from multiple sources over time.
In practical terms during a visit, ALARA may look like:
- confirming there is a clinical question the image is expected to answer;
- checking whether existing images are adequate;
- selecting the fewest views that can provide essential information;
- limiting the beam to the area being examined (the ADA recommends rectangular collimation for this);
- positioning you correctly so the image is right the first time;
- using appropriate receptor and technique choices for the diagnostic task;
- avoiding retakes caused by preventable positioning or processing errors;
- reserving 3D CBCT for questions that lower-dose images cannot answer.
ALARA is not a promise of zero risk. It is a professional standard for balancing useful diagnostic information with responsible radiation stewardship.
Lead aprons and thyroid collars: what has changed
Many people remember a heavy lead apron at every dental X-ray. Guidance on shielding has shifted, and Canadian and American advice currently differ.
| Source | What it says |
|---|---|
| American Dental Association (2024) | No longer recommends lead aprons or thyroid collars for dental imaging, because they can block the beam, cause retakes and increase total exposure |
| Health Canada, Safety Code 30 (2022) | Patients must be provided with a thyroid shield when it will not interfere with the required diagnostic information, which is especially important for children |
| Canadian Dental Association | Calls for appropriate patient shielding as part of radiation control |
Dental offices in Canada follow federal and provincial requirements, so you may still be offered a thyroid collar, particularly for a child. What matters most is not the apron itself but beam limitation, careful positioning and taking only the images needed. If you have a preference or a concern, ask the team what they use and why.
Pregnancy, children and other special situations
Pregnancy and childhood do not automatically forbid dental X-rays, but they do call for clear communication and careful justification.
Pregnancy
The Canadian Dental Association notes that elective procedures may be deferred until after pregnancy, while pregnant patients who need essential or emergency dental care should receive the minimum number of radiographs needed for diagnosis. Health Canada's Safety Code 30 cites that guidance and notes that the level of radiation to the fetus from dental X-rays is extremely low when the abdomen is not directly exposed.
If you are pregnant, think you might be, or are trying to become pregnant, tell the dental team before imaging. Ask why the image is needed now, whether care can safely wait, and which views are essential for treatment decisions. Untreated dental infection during pregnancy is also a risk, so postponing a needed image is not always the safer choice.
Children and teens
Children and adolescents may require imaging for development, trauma, decay risk or orthodontic assessment, but selection should still be individualized. Younger patients are generally considered more sensitive to ionizing radiation over a lifetime, which is one reason professional guidance emphasizes justification and optimization rather than routine screening with unnecessary exposures. It is also why Safety Code 30 stresses thyroid protection for children.
Other situations
- Recent imaging elsewhere: mention recent medical or dental imaging so your dentist can decide whether new dental images are needed.
- Cancer treatment or radiation therapy: tell the team about any history of head and neck radiation; it affects both imaging choices and dental care.
- Frequent imaging for ongoing treatment: if you are having implant, root canal or orthodontic care, ask how many images the plan is likely to need.
- Anxiety about radiation: it is reasonable to ask for the reason behind each image. A clear explanation is part of informed consent.
Questions to ask before imaging
Asking questions helps you understand both the reason for imaging and the safeguards being used. Useful questions include:
- What are you looking for that you cannot see in my mouth? The answer should connect to a symptom, finding, risk factor or planning need.
- Could recent images from another office be used instead? Bring copies or ask for electronic transfer when possible.
- Which views are essential today? Ask whether any proposed images can wait without delaying needed care.
- How will the result change my options? Imaging is most useful when it can affect diagnosis, monitoring or treatment choices.
- What should I tell you about pregnancy, childhood health or prior radiation exposure? Share relevant details before the exposure is taken.
You can also ask how findings will be explained and whether images will be stored for future comparison. Digital records can support follow-up, but storage convenience alone is not a reason to take radiographs without clinical need.
Dental X-rays at our Truro office
Landmark Dental Care is a family general practice at 125 Queen St in downtown Truro, serving Truro, Bible Hill and Colchester County. We use digital X-rays as part of exams and emergency visits, and images appear on screen during the appointment so your dentist can walk you through what they show.
If you are new to the practice, ask your previous dentist to send recent X-rays before your first visit; it may reduce the number of new images you need. For questions that standard X-rays cannot answer, the practice also offers 3D CBCT imaging, which is used selectively because of its higher dose. If you are wondering about coverage for X-rays under the federal program, see our Canadian Dental Care Plan page and call to confirm current participation and billing.
FAQ
Are digital dental X-rays completely risk-free?
No. Digital dental X-rays use ionizing radiation, even though exposures for dental imaging are generally low compared with many medical imaging exams. Safety depends on prescribing images only when clinically useful and applying dose-reduction practices after that decision is made.
Is a dental X-ray more radiation than a chest X-ray?
No, a single bitewing uses much less. RadiologyInfo estimates about 0.005 mSv for an intraoral dental X-ray and about 0.1 mSv for a chest X-ray, though actual doses vary with equipment and the number of images taken.
How often should I have dental X-rays?
There is no universal schedule that fits every patient. Frequency should reflect your oral health, age, disease risk, symptoms and whether previous images still answer the clinical question. Your dentist should explain why imaging is recommended at a given visit.
Should I refuse X-rays if I am pregnant?
Not automatically. Tell the dental team about pregnancy first. Elective imaging may be deferred, while essential or emergency care may still require the minimum radiographs needed for diagnosis.
Why didn't I get a lead apron at my dental X-ray?
Some dental organizations, including the ADA since 2024, no longer recommend lead aprons or thyroid collars, because they can get in the way of the beam and lead to retakes. In Canada, Health Canada still calls for a thyroid shield when it will not interfere with the image, so ask the team about their approach.
Next step
If you have questions about imaging during an exam or want to understand how radiographs support diagnosis, learn how we use digital dental X-rays or call 902-893-2919 to discuss an appointment at 125 Queen St in Truro. You can also reach us through our contact page.
References
- Canadian Dental Association: Control of X-Radiation in Dentistry
- Health Canada: Radiation Protection in Dentistry — Safety Code 30 (2022)
- American Dental Association: X-Rays/Radiographs
- American Dental Association: ADA releases updated recommendations to enhance radiography safety in dentistry
- RadiologyInfo.org: Radiation Dose
- U.S. FDA: ADA/FDA Guide to Patient Selection for Dental Radiographs
- ADA/FDA: Dental Radiographic Examinations (patient selection guidance PDF)
This article provides general educational information and is not a diagnosis or a substitute for care from a dentist or other qualified health professional.
About this guide
This article was written and reviewed by the Landmark Dental Care Team at Landmark Dental Care, 125 Queen St, Truro, NS B2N 2B4. It is general patient education and is not a diagnosis or a substitute for an examination. If you have pain, swelling or a change in your mouth, call us at 902-893-2919 so a dentist can assess you.