X-rays Are Scary! Or Are They?

Used safely, with modern equipment, by a trained professional, there is nothing to fear when it comes to dental x-rays. Radiation is all around us, and may even be sitting in your fruit bowl.

The humble banana is often used to compare radiation levels to it, in an effort to help us understand how much radiation is in things. It even has a name - the Banana Equivalent Dose (BED). Ionising radiation (that type that damages living cells), is measured using units called “Sieverts (Sv).” More commonly, we measure radiation using micro-Sieverts (µSv). 1 µSv is 0.000001 sieverts (that’s a millionth of a Sievert!). Just by living on Earth, you absorb about 2000 µSv each year. In orthodontics, we commonly take two X-rays, a long horizontal one that shows all your teeth and bone (panoramic X-ray), and a vertical one that shows us the side of your skull (lateral cephalogram). A panoramic X-ray is about 15 µSv and a lateral cephalogram is about 3 µSv. If you fly from New York to Tokyo, you’ll absorb about 150 µSv during the flight. That’s almost 10 times what you would get from your orthodontic X-rays.

So, let’s get back to bananas. If you eat one banana, you absorb about 0.1 µSv. Can you work out how many bananas you’d need to eat to absorb the same levels of radiation as your orthodontic X-rays? X-rays…not scary after all, right?

Updated July 2026: X-rays are part of how we plan safe, accurate treatment for every age group. You can read more about early assessments on our children's orthodontics page, see how a full work-up fits into our process, or ask us anything at a free Smile Assessment.

What each orthodontic X-ray actually shows

The post above puts the radiation into perspective. It is worth explaining what we are actually looking for, because the images do a lot of quiet work behind a good treatment plan.

The panoramic X-ray

The panoramic image, taken as the machine travels in a smooth arc around your head, gives us a single wide view of all your teeth and the jawbones that hold them. It shows teeth that have not yet come through, including wisdom teeth, the position and length of the roots, and the health of the surrounding bone. For children and teenagers it helps us see which adult teeth are on their way and whether any are heading in the wrong direction, so we can plan around growth rather than react to it later.

The lateral cephalogram

The lateral cephalogram is a side-on view of the skull. It lets us measure the relationship between the upper and lower jaws and the angle of the front teeth, which tells us how a bite is put together rather than simply how it looks from the front. These measurements guide decisions about how teeth should be moved, and they give us a baseline to compare against as treatment progresses.

Smaller and three dimensional images, when they are needed

Sometimes we take a small close-up X-ray of a single area, or, in more complex cases, a three dimensional scan that shows a tooth or root from every angle. We only take the images a particular case genuinely needs. The guiding principle across dentistry is to use the smallest amount of imaging that still allows a safe, accurate diagnosis, and to have a clear clinical reason for every image taken.

Keeping everyday exposure in perspective

As the post explains, low levels of radiation are simply part of living on Earth. It reaches us from the ground, from the air, from the food we eat, and more of it the higher we travel, which is why a long flight adds a measurable amount. Set against that constant background, the brief images used in orthodontics are a small and carefully justified addition, taken with modern equipment designed to keep the dose low. Understanding where the images sit against everyday life is usually enough to put the worry to rest.

If you or your child needs orthodontic records, we will always explain what we are taking and why before anything happens. You can read how imaging fits into a full assessment on our children's orthodontics page, or ask us anything at a complimentary Smile Assessment. We are on (09) 520 1880 if you would like to talk it through first, and no referral is needed to get started.