Posts for: November, 2015
One of the most widely used forms of dental imaging is the bitewing x-ray. So called because of the shape of the device that holds the exposable film a patient clenches between their back teeth, the bitewing x-ray is an effective means for detecting the earliest stages of tooth decay.
These early signs are small lesions on a tooth surface caused by mineral loss in the enamel. While we can identify them on front teeth through visual examination or bright lighting, they’re nearly impossible to see on the biting surfaces of back teeth. The bitewing x-ray solves this problem.
During the procedure, a narrow beam of x-rays is directed at the back teeth area. Since X-rays can transmit through solid matter, they pass through the teeth and gums to expose the film attached to the bitewing assembly.
X-rays pass through matter at different rates depending on the density of the tissue — a slower rate for harder tissues like teeth and bone and a faster rate for soft tissues like the gums. As a result, x-rays through teeth expose less of the film and appear as a lighter image than the gums. This difference is so precise even a tooth’s softer dentin appears slighter darker than its harder outer enamel.
This precision helps us identify decay lesions. Because the lesions on the enamel are less dense than the normal enamel, they’ll appear as dark spots. By detecting them at this stage we have a better chance for reversing the effects of decay or at least minimizing damage that’s already occurred.
Because x-rays emit radiation, there’s a natural concern about over-exposure and we go to great lengths to reduce it. Children may undergo a bitewing x-ray twice a year for developing teeth, while adults with healthy teeth are typically x-rayed just once a year. Advances in digital film and other technology have also helped lower the exposure rate.
Today’s standard 4-film bitewing x-ray produces about four days worth of what we receive on average from normal background radiation, so the health risk is quite negligible. The benefit, on the other hand, is much greater — the early detection of tooth decay could ultimately save a tooth.
A few days before the Oscars, Vanity Fair magazine asked Academy Awards host Neil Patrick Harris to name his most treasured possession. Was it his Tony award statuette for best leading actor in a musical? His star on the Hollywood Walk of Fame? The stethoscope he wore while playing teenaged doctor Doogie Howser on TV? No, as it turns out, the 41-year-old actor’s most treasured possession is… his wisdom teeth. Yes, you read that correctly. “Oddly, I still have my four wisdom teeth,” Harris said. “I refuse to let them go or I’ll lose my wise parts.”
How odd is it for a 41-year-old to have wisdom teeth? Actually, not that odd at all. While it is true that wisdom teeth are often removed, there’s no one-size-fits-all approach to this. It all depends on whether they are causing problems now, or are likely to cause problems in the future.
The trouble wisdom teeth cause is related to the fact that they are the last molars to come in, and that molars are large in size. By the time wisdom teeth appear between the ages of 17 and 21, there often is not enough room for them in the jaw. Sometimes it’s because you may have inherited a jaw size that’s too small for your tooth size; and generally speaking, the size of the human jaw has evolved to become smaller over time.
If room is lacking, the adjacent molar (that came in earlier) can interfere with the path of eruption — causing the wisdom tooth to come in at an odd angle. The wisdom tooth can hit up against that other tooth, possibly causing pain or damaging the adjacent tooth. This is known as “impaction.” Sometimes the wisdom tooth breaks only partway through the gum tissue, leaving a space beneath the gum line that’s almost impossible to clean, causing infection. A serious oral infection can jeopardize the survival of teeth, and even spread to other parts of the body.
If a wisdom tooth is impacted, will you know it? Not necessarily. A tooth can be impacted without causing pain. But we can see the position of your wisdom teeth on a dental x-ray and help you make an informed decision as to whether they should stay or go. If removal is the best course of action, rest assured that this procedure is completely routine and that your comfort and safety is our highest priority. If there is no great risk to keeping them, as Neil Patrick Harris has done, we can simply continue to monitor their condition at your regular dental checkups. It will be particularly important to make sure you are reaching those teeth with your brush and floss, and that you keep to your schedule of regular professional cleanings at the dental office. All healthy teeth are indeed worth treasuring.
If you would like more information about wisdom teeth, please contact us or schedule an appointment for a consultation. You can learn more by reading the Dear Doctor magazine articles “Wisdom Teeth” and “Removing Wisdom Teeth.”