To all of those who read this newsletter, thank you. I hope you find this monthly newsletter educational and interesting; perhaps it may even answer some questions about oral health that you may have been pondering. If you have any dental questions or topics you would like me to write about, please let me know! This month I want to talk about the different types of dental radiographs (aka X-rays), the appropriate intervals to take them, and safety facts.
First and foremost, dental radiographs are a diagnostic aid that help dentists identify various tooth-related structures that are sometimes not visible to the eye during an exam. Radiographs, or X-rays, allow us to see the roots of teeth, the underlying bone, the restorative margins of fillings and crowns, and the depth of enamel and dentin in relation to the nerve of the tooth. X-rays alone cannot diagnose a condition, but certainly help immensely in the diagnosis of dental conditions. An understanding of the big picture: clinical examination, radiographic examination, and knowledge of symptoms and medical history allows a diagnosis to be made.
There are several “styles” of x-ray that can be taken:
Periapical radiograph (PA): a single film that shows the roots of a tooth or several teeth. Often taken as part of a full mouth series or on an as needed basis for a tooth with symptoms. PAs are helpful for identifying root abscesses and visualizing root canal treated teeth.
Bitewing radiograph: a single film often taken in a set of four that shows the “in-between” areas of enamel and dentin that are not visible on pre-molars and molars. Bitewings are helpful for seeing the depth of a cavity in relation to the nerve of the tooth.
Panoramic radiograph: A large single film taken with a specific machine that visualizes the entire maxilla (upper jaw bone) and mandible (lower jaw bone). These films can identify underlying conditions of the jaw and sinuses like cysts and tumors.
Cone-beam radiograph (CBCT): A large “3-D” film taken with a specific machine that shows series of films taken in discreet sections that visualize the three dimensions of teeth in relation to other anatomical structures like bone and nerves. CBCTs are helpful for implant placement or understanding the complex root system of a tricky tooth.
Full-mouth series: A series of 14 periapical films and 4 bitewing films taken every five years to visualize a patient’s entire dentition for a comprehensive look at all of the roots of all teeth, bone quality, and underlying anatomical structures around the upper and lower jaw.
Our practice operates according to the recommendation of the American Dental Association that low-risk patients should have routine bitewing examination (a quick set of 4 films) every 24-36 months and a full mouth series (a comprehensive set of 18 films) every five years. The radiation exposure for these routine radiographs is incredibly minimal with digital x-ray technology and the benefits far outweigh the possible risks.
Digital dental x-rays expose patients to roughly 70% less radiation than conventional film x-rays. A single PA x-ray exposes someone to 0.005 mSv of radiation which is equal to the same amount of radiation once is exposed to from eating two bananas. Humans experience more radiation from one day out in the sun’s rays than they do from a full series of x-rays. In a nutshell, the amount of radiation that we experience from routine dental x-rays is very miniscule and less significant than many people understand or expect.
Furthermore, if patients refuse routine radiographic examination, they put their dentist at risk of losing their license. Patients who refuse occasional x-rays put the dentist in a situation of practicing willful negligence; this would be like your cardiologist relying solely on feeling your pulse instead of listening to your heartbeat through a stethoscope.
Finally, a dentist who accepts the responsibility of treating a patient can be held liable, in a court of law, for willful negligence if they underdiagnose or misdiagnose a condition due to lack of radiographic information. Please keep in mind that when Dr. Krist and I recommend x-ray examination, it is because we want to be thorough and cover all bases of diagnoses.
Dr. Krist and I understand that nobody truly wants to have x-rays taken often and they can be an uncomfortable topic to discuss with patients. However, we have an ethical and moral obligation to treat our patients with the respect and attention to detail that they deserve. Thank you for reading and please call me or Dr. Krist if you have any questions or concerns!
Dr. John Obeck