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Why Do Dentists Take X-rays And What Does That Have To Do With Bananas?!

I am sure most people know that x rays can be used to diagnose problems like a broken bone for example, but why do dentists take them when you haven’t got any broken bones?

Dentist take x rays to help us find out any problems with your teeth and jaws. X-rays are commonly used to see things “deeper inside your body” where you can’t see just with your eyes. It is for these reason that they can be so helpful for us as dentists to diagnose problems.

X-rays work because hard structures like teeth and bone don’t let the x-ray travel through them and leave a white area on the picture. Areas with spaces or soft tissue allow the x-rays to pass through and make a dark area on the picture and this gives us the image we call a radiograph.

Why do we take them?

The most common reasons to take dental radiographs is to check for decay in your teeth.

Tooth Decay

Tooth decay can be really difficult to spot particularly in its early stages, as it starts beneath the surface of the tooth, undermining and eating away at the inner structure, often without giving the patient any signs or symptoms that there is a problem.

As dentists we are trained to look for the subtle changes on the tooth that may indicate tooth decay but even with bright lights and magnifying lenses it can still be very difficult to spot tooth decay on the hard to see areas in between teeth, and this is where radiographs come in.

Look at this example.

To the untrained eye the tooth may look and feel fine in your mouth but taking a radiograph shows a dark shadow (see arrow) indicating that there is quite a lot of decay in this tooth. Furthermore, the patient was completely unaware of any problem and didn’t have any pain or sensitivity, despite the amount of decay present. Luckily, we could fix it easily with a nice white filling to beautifully restore this tooth back to health.

Gum disease

Gum disease is really common in the UK with 45% of adults being affected by it.

Gum disease causes destruction of the gum and bone that hold in your teeth and if left untreated can result in tooth loss. We can use x-rays to check the amount of bone surrounding your teeth and intervene before it becomes a real problem.

Diagnose infection

Toothache hurts! Sometimes it can be really difficult to pin point where the pain is coming from and we can use radiographs to see underneath the tooth to check if there are any signs if dental infections, like an abscess, and ensure we treat the right tooth.

Are Xray’s safe?

Yes, dental x-rays are safe. It is important to remember that any x-ray that you get carries a very small dose of radiation with it. Particularly with dental radiographs this dose really is tiny. To put this in relative terms, we measure the radiation dose in units called sieverts Sv, or more commonly in dentistry where the doses are really small milli sieverts mSv.

At Borland and Morton we have the digital sensors which allow us to reduce the exposure much lower than old film radiographs meaning the dose from a standard small dental radiograph is reduced by up to 75%

To give this some context, we can compare the amount of radiation dose of a dental radiographs to everyday sources of background radiation like......eating a banana! Yes, believe or not banana contain a very small amount of natural background radiation. This is because bananas are naturally high in potassium, which is essential for maintaining your bodies electrolyte levels, however, some of this potassium will be in the form of a isotope called potassium-40 which is slightly radioactive. Now before you go off bananas for good, its important to bare in mind how little radiation is actually from bananas - you would need to eat 100 bananas in one day to equal the average daily dose of background radiation. So it really is very very small!

So we can actually compare how many bananas you would need to eat to give a same dose of radiation.

Eating a banana is about 0.0001 mSv

A standard small dental radiograph is

0.004 – 0.006 mSv (50 bananas)

A large dental panoramic radiograph is

0.02 mSv (200 bananas)

Your average daily exposure to background radiations is

0.01 mSv (100 bananas)

A flight from new York to LA is 0.04 mSv (400 bananas)

Living in a stone, brick or concrete building for 1 year 700 bananas 0.07 mSv

So relatively speak xrays are really very safe. But it is important that as dentist that we only take radiographs when there is a good reason or justification to do so and there are great guidelines that we follow from the faculty of general dental practitioners.

The FGDP guidelines recommend radiographs are taken at least every 2 years to check for decay and more frequently if you are a higher risk of decay

Taking radiographs play an important role for us as dentists to help diagnose if you have any problems or pain in your teeth to pin point and identify where and what the problem is. They helps us intercept problems before patients are often aware of them, by allowing us to spot decay at an early stage and therefore allowing us to intervene and fix your teeth at an earlier stage. They also are very useful for monitoring any conditions such as gum disease to make sure things aren’t deteriorating. So if you need some xrays taken don’t worry about it. Even if we have to leave the room (we can take quite a lot in one day).

That’s why is is really important to attend for your dental check ups regularly to ensure your teeth stay in tip top shape.

Call now on 01698 285726 to book your check up or complete our online form and we will arrange at time for your dental check up appointment.

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