A digital dental X-ray delivers roughly 0.005 millisieverts, a small fraction of the 2–3 millisieverts a person receives from natural background radiation each year, and comparable to a few hours of ordinary living. Dental X-rays are taken only when they will answer a specific clinical question — decay between teeth, infection at a root tip, bone level, or the position of an unerupted tooth — none of which can be seen by looking.
Putting the dose in perspective
| Source | Approximate dose |
|---|---|
| Single digital dental X-ray | ~0.005 mSv |
| Full panoramic (OPG) | ~0.01 mSv |
| Natural background radiation, per year | ~2–3 mSv |
| Chest X-ray | ~0.1 mSv |
| CT scan of the abdomen | ~8 mSv |
Swipe the table sideways to see every column.
Digital sensors reduced dental X-ray doses substantially compared with the film they replaced. Our clinic uses digital radiography, which also means the image appears immediately and can be shown to you on screen.
What an X-ray shows that an examination cannot
- Decay between teeth, where the surfaces touch and cannot be seen or probed.
- Infection at the tip of a root, which is inside bone.
- Bone level around teeth — the actual severity of gum disease.
- Position and angulation of unerupted or impacted teeth.
- Decay underneath an existing filling or crown.
- Cysts and other lesions that produce no symptoms at all.
Children and pregnancy
Children are X-rayed only when there is a specific question, such as decay between closely spaced back teeth or a missing permanent tooth. The dose is small and the exposure is collimated to the area of interest.
In pregnancy, non-urgent X-rays are usually deferred to after delivery. Where one is genuinely necessary — an infection needing treatment — it can be taken safely with a lead apron and thyroid collar. An untreated dental infection poses a far greater risk to a pregnancy than a shielded dental X-ray.
Reasonable questions to ask
- What question will this X-ray answer?
- Is this digital or film?
- Can I see the image and have it explained?
- Do I already have a recent X-ray that would do?
Questions we get asked
How often should dental X-rays be taken?
There is no fixed schedule. It depends on your decay risk and gum health — someone with frequent new cavities may need bitewings every 12 months, while a low-risk patient may go two to three years.
Can I refuse a dental X-ray?
Yes, and you should be told what that means. Some treatment can proceed without one; other treatment, such as root canal or implant placement, cannot be done safely without imaging.
Do I need a lead apron?
Guidance in many countries no longer requires routine aprons for dental X-rays because scatter is minimal and collimation has improved. They are still commonly used, and are standard practice where a patient is or may be pregnant.