Are Dental X-Rays Safe? How Often You Really Need Them
- Star Light Dental
- May 28, 2026
- [email protected]
It is a fair question. You come in for a check-up, and part way through you are asked to bite on a small sensor while everyone else leaves the room. Is it safe? Is it necessary? And why does the dentist want more this year?
The short answers are yes, sometimes, and it depends on your risk. Here is the longer version.
1. How Much Radiation Is in a Dental X-Ray?
Very little. Everyone in Australia receives around 1.5 millisieverts of natural background radiation each year from the ground, the air, food and space. A pair of routine bitewing X-rays delivers roughly the same dose as one ordinary day of that background exposure. A full panoramic X-ray of the jaws is equivalent to a few days.
For comparison, a long-haul flight from Sydney to Europe exposes you to considerably more radiation than a set of dental X-rays. Modern digital sensors have also cut doses substantially compared with the old film X-rays many of us grew up with.
2. What X-Rays Show That Eyes Cannot
- Decay between the teeth, which is where most adult decay starts and which is invisible until it is large.
- Decay under existing fillings and crowns.
- Infection or an abscess at the tip of a root, often before it causes pain.
- Bone loss from gum disease.
- Impacted wisdom teeth, extra or missing teeth, and how children’s adult teeth are developing.
- Cysts, cracks in roots and other problems within the jaw.
Without X-rays, a dentist can examine only about two thirds of each tooth.
3. The Main Types
- Bitewings: small X-rays of the back teeth, used to find decay between teeth and check bone levels. These are the routine check-up X-rays.
- Periapical: shows one or two whole teeth from crown to root tip, used to investigate pain or infection.
- Panoramic (OPG): one image of all the teeth and both jaws, used for wisdom teeth, children’s development and treatment planning.
- 3D cone beam CT: a higher-dose scan reserved for specific needs, such as implant planning or complex surgery.
4. How Often Do You Really Need Them?
There is no fixed schedule that suits everyone, and X-rays should never be taken just because a year has passed. The principle dentists follow is to keep exposure as low as reasonably achievable, which means taking X-rays only when they will change what we do.
- Low risk (no recent decay, healthy gums): bitewings roughly every two years, sometimes longer.
- Higher risk (recent decay, many fillings, gum disease, dry mouth): every six to twelve months until things are stable.
- New patients: usually a baseline set, unless you can bring recent X-rays from your previous dentist.
- Children: based on their decay risk and stage of development.
5. Pregnancy and Children
Routine X-rays are normally postponed during pregnancy. If one is genuinely needed to diagnose pain or infection, the dose is tiny and the beam is aimed at the jaw, a long way from the baby, so it can be done safely. Our article on dental care during pregnancy has more detail.
Children are more sensitive to radiation than adults, so we take only the X-rays that are needed, using the smallest sensor and the lowest setting that will give a clear image.
6. Can I Say No?
Yes. It is your decision and we will always explain why we are recommending an X-ray and what we expect it to show. Bear in mind that without one, some problems simply cannot be diagnosed, and decay between teeth that is missed at an early stage is the kind that ends up needing a root canal or a crown. If cost is the concern, most health fund extras cover X-rays under general dental, and they are covered for eligible children under the CDBS.
Questions About Your X-Rays?
Ask us at your next visit. We are happy to show you your X-rays on the screen and explain exactly what we are looking at. Call Star Light Dental in Prestons on (02) 9432 2833 or book online.