A frequently asked question at our office is, “How often should I have x-rays taken and why do I need them?” This is a great question!
Dental x rays are one of the most important parts of maintaining good oral health because they give the dentist a picture of what is going on beneath the surface of the teeth. They also allow me to see what is going on between your teeth. Having x-rays taken regularly can diagnose and prevent serious complications that would otherwise go undetected.
As a general rule of thumb, you should get a set of bitewings taken once a year, and a full mouth series (FMX), which includes 10 to 18 intra oral X-rays and one extra oral (panoramic) X-Ray once every 3 - 5 years. Of course, if you are experiencing pain or other problems/concerns/suspicions in between x rays, additional ones may need to diagnose. In today’s blog I will explore the risk of radiation from dental x-rays and the factors that determine how often you need x-rays taken.
HOW MUCH RADIATION IS IN A DENTAL X-RAY?
You are exposed to low dosage radiation all day, every day and your body is designed to deal that exposure. Media information often lumps all x-rays into one category, which leads some to worry about the exposer risks dental X-rays will add.
The fact is that X-rays save teeth and lives by allowing diagnosis for dental disease at its earliest detection. If as dentist we relied on visual or patient description alone your health would be greatly comprised. That being said, yes, dental X-rays use radiation to image the teeth and bones.
Unlike x-rays machines when we were young, modern digital x-rays are extremely low in radiation. Let’s break this down so you can see why we use the term extremely low. When you are measuring radiation the measurements are in milliseverts (mSv). To illustrate someone's normal daily exposure the Mayo Clinc put together data to compare the radiation from dental x-rays to the radiation we are exposed to everyday. Their findings are below:
Eating a banana 0.1 mSv
Average Year of Watching TV 10 mSv 4- Bitewing X-rays 0.038 mSv
5 Hour Airline Flight 25 mSv Full mouth dental X-rays0.150 mSv
1 yr. living in a brick home 70 mSv
Avg Yearly dosage from food 400 mSv
(Source BBC and MayoClinic)
As you can see a dental x-ray has the equivalent radiation to eating bananas! This is why we say that in comparison to exposure you have throughout a normal day to radiation, dental x-rays are extremely low.
FACTORS THAT DETERMINE HOW OFTEN YOU SHOULD HAVE DENTAL X-RAYS TAKEN:
Do you have exisitng restorations or previous decay?:
The number one factor for determining how often you need dental x-rays taken is the amount of fillings or restorations you already have in your mouth. If you have multiple fillings or other dental restorations, you need to have x-rays taken more often. It is important not only to monitor the state of the fillings and restorations you have, but also to keep an eye on the surrounding teeth because you are more prone to decay.
Certain ages are more prone to specific complications, and therefore need to have x-rays taken more frequently to check for decay or other possible complications. An example of this would be around age 17 wisdom teeth usually come in, and need to be looked at through x-rays to see if they are causing problems and need to be removed. Also, children’s teeth are more susceptible to cavities and need to be x-rayed more often.
Overall Oral Health:
Plain and simple: Some people are more prone to cavities and/or gum disease. People that have shown that they are at a higher risk of getting cavities or gum disease need to have dental x-rays taken more often, to catch signs of these at the earliest stages possible. On the contrary, patients that have shown that they are not cavity-prone can go longer in between x-rays.
Previous Operations and Procedures:
Patients that have had serious oral surgeries or restorations need to keep a closer eye on what is going on with their oral health than others. X-rays not only detect cavities but also can detect other complications like bone degeneration that could be from previous extractions or other things. For example, patients with dental implants need to have x rays taken regularly to monitor any irregularities or changes.
Some medications can cause dry mouth, and make you more susceptible to decay. Other medications can cause other complications to oral health, such as weaker bone. People taking medications that affect their oral health need to have x rays taken more often.
Unfortunately (or maybe, fortunately), where you grew up may influence how often you need to have x-rays taken. Some cities have higher amounts of fluoride in the water source, which has shown to promote oral health in those areas. If you grew up somewhere that fluoride wasn’t a part of the drinking source, you should get x-rays more often to keep an eye on decay.
Undergoing Cancer Treatment:
Having undergone cancer treatments is an important factor in determining how often you should have dental x-rays taken. Some cancer treatments such as chemo and radiation therapy can have negative effects on teeth and surrounding bone and should be monitored. Always let your dentist know what type of cancer treatments you have undergone so that they can plan your x-ray treatment accordingly and safely.