My Dentistry Blog
Posts for tag: x-rays
For decades, dental x-rays have helped us accurately diagnose and treat a wide array of dental diseases and conditions. But even with recent advances in digital imaging, the traditional x-ray does have one drawback: its two-dimensional view doesn’t always provide the “big picture” that a three-dimensional viewpoint can provide.
But a new type of x-ray technology can do just that: known as cone beam computed tomography (CBCT), these machines record hundreds of digital images as a cone-shaped beam of x-ray energy is projected through a device that rotates around a person’s head. A computer then assembles the images into a single three-dimensional image that can be manipulated on screen to view from various angles. Not only does this provide greater context and detail, it does so with no more radiation exposure than a standard 20-film digital full-mouth x-ray series.
While CBCT hasn’t replaced the traditional x-ray, it’s making its mark in a number of specialized areas of dentistry. The following are just a few of the ways CBCT is improving both accuracy and treatment outcomes.
Orthodontics. CBCT can provide a much more detailed view of the entire jaw; this can help us determine the best locations for realigning teeth safely and effectively.
Dental Implants. With a CBCT scan we can precisely locate nerve canals, sinuses and adjacent teeth before implant surgery to locate the best position for the implant.
TMD Treatment. To help develop the best treatment approach for alleviating the pain and dysfunction of temporo-mandibular joint disease (TMD), a CBCT scan can provide us detailed information on how the disease is affecting a patient’s joints, teeth, sinuses and airway.
Impactions. An impacted tooth can exert damaging pressure against the roots of neighboring teeth. A CBCT scan allows us to observe the impacted tooth from various vantage points to determine the best treatment approach for neighboring teeth, nerve canals and sinuses.
If you would like more information on CBCT technology, please contact us or schedule an appointment for a consultation. You can also learn more about this topic by reading the Dear Doctor magazine article “Getting the Full Picture With Cone Beam Dental Scans.”
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.