Patient’s Questions about Dental X-ray’s and Radiation
Gabriel T Duncan, DDS
I am frequently asked about dental radiographs; their safety from a radiation standpoint as well as why we take them, and if it is okay not to take them. We also get asked if its ok to bring existing x-rays from another office (yes, this is fine if they are current and give us the information we need). So, in this short post I am going to share some information about how much radiation is given off during a dental x-ray as well as why we take them.
Why are x-rays important? When we do a clinical exam, we see only what our eyes will allow us to see: only part of the tooth and the outside of the tissue is visible. Yet often the first sign of oral disease is not seen clinically but in a radiographically. When I recommend dental radiographs for my patients it is because I need a complete view: the teeth and nerves within, the gum tissue, and the bone. I need these images to accurately diagnose and plan treatment. I want my patients to know and feel confident that when they do have dental radiographs taken, it is with the lowest possible radiation dose, and with the highest safety and quality equipment available in the industry.
How much radiation is in a dental x-ray? It is a very, very, tiny dose. It is such a low dose, that the risk of having serious health complications from a condition that we are trying to detect with the x-rays is significantly higher than any potential health problems arising from taking the x-ray itself. Even years ago, when we did not have digital x-rays (at Spring Smiles we only use the newest digital radiology equipment) it was still an extremely low dose of radiation. Now, with the digital equipment we have at Spring Smiles, it is about 90% less radiation. This makes taking needed x-rays at appropriate time intervals safe for both children and adults.
Below are some approximate numbers to help clarify and to give context: If you were to go the hospital and have medical CT scan taken, the dosage of radiation that would be used would be in a range of around 2100-6000micro sieverts (micro means 1/millionth) of a sievert. And a Sievert is the unit of measurement in radiology. Knowing this I will now compare this to various dental radiographs that we take at Spring Smiles.
-A 3-D dental Cone Beam CT scan delivers the most radiation of any image in dentistry. It also provides great value and a huge amount of diagnostic information. This would be somewhere between 90-120 micro sieverts. To put this in practical terms this is roughly the amount of background radiation you would get when taking across country flight from LA to New York.
-A full mouth series of x-rays; generally, 18 individual 2-Dpictures of the teeth and underlying structures: about 80 micro sieverts. (roughly equivalent to a 2-hour flight)
-A set of four cavity-detecting bitewings: (a 1–2-hourflight)
Dental radiographs should only be taken when necessary. When recommended by the dentist the benefit of having the diagnostic information far exceeds the small risk as there are some dental diseases (decay, bone disease, even cancer) that are caught only by having access to the information they provide.
If someone has questions about dental x rays, I encourage them to give us a call here at Springs Smiles. Reach out and I will be happy to discuss them in more detail.