When I was younger, I always wanted to predict the future, find a secret world, or notice things others couldn't see. But, the cape attracted a lot of unflattering comments, so I became a dentist instead. Nowadays, I just have X Ray vision. X Rays, or more specifically radiographs, have been around since 1895. When electrons from electricity hit a tungsten target, tiny bundles of energy are released much like sparks when metal hits flint. This energy called radiation is guided to hit another target like film or digital receptor. If some of these energy bundles get stopped by whatever (or whomever) is dense enough to get in their way, a pattern is recorded. This pattern forms a picture- a radiograph.
In medicine, radiation is used for a variety of reasons from virus mapping to cancer treatments. My children and I just watched an interesting documentary on gamma radiation called The Incredible Hulk, but I believe this technology is still experimental. Kidding aside, while radiation has its place in medicine it also has received a bad rap in the popular media. So, let's concentrate on dental radiographs – the X rays you get at the dentist.
Dental Radiographs come in two forms, small intraoral for looking at a few teeth at a time and extraoral for looking at a portion or whole jaw or skull. Small intraoral films or digital sensors look for cavities or bone height. These X rays can pick up changes in tooth density that may later result in cavities or millimeter changes in bone to monitor healing or pathology. No modern dentist today can imagine doing root canal therapy or restorative dentistry without the aid of X rays. Extraoral radiographs are used to assess growth or bone pathology. Orthodontists and Oral Surgeons use these radiographs to plan treatment strategies and monitor progress.
So when does a child need X rays? This question has been researched and regulated carefully. According to ADA Guidelines, X rays are indicated when a benefit is anticipated. In other words, don't take 'em if you don't need 'em! For children four and older, the dentist categorizes a child by cavity risk then takes periodic X rays designed to monitor that risk. Children with active decay or recent decay history need X rays every 6 months. Children with no recent history of decay may use X rays to monitor for decay once every 12 or 18 months. Risk for disease is measured by history, plaque index, brushing habits, overall health, age, ability, or parental help. And you guessed it, risk varies over time!
But what about the radiation? For dental radiographs you are talking miniscule. The average FILM X ray uses 0.06 mGray to produce. Digital X rays use a quarter to half that amount. As a comparison, a dental technician can receive 85mGray every year to be below the safety threshold. UCLA published a study stating a set of dental X rays can been compared to about 8 hours in the sun or about 3 months of cosmic radiation at our altitude. If you compare that to the benefit of preventing a serious disease which can lead to root canals, extractions or worse, you come upon you own cost/benefit ratio.
So, next time you are at your dentist, ask to see your child's radiographs and have them interpreted for you. There is a whole secret world you can peer into that will show you some things about your family's health you never noticed before. They may even allow you to alter your child's future – without the cape!
Dr. Greg is the most experienced board certified pediatric dentist in Fort Collins, Colorado. His extensive training began with graduating with honors from the dental school at the University of Iowa in 1996 and a residency program at the Children's Hospital of Denver. His professional interests include infant dental care and hospital dentistry and he is a Technical Advisor for Colorado's Cavity Free at Three initiative. He is also a founding member of the PVH Cleft Lip and Palate Team, and regularly coordinates oral care with area physicians in and out of the hospital. To learn more about Dr. Greg and his practice, visit www.biggrinswithdrgreg.com. |
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