Dentists use x-rays to detect dental problems such as cavities, gum (periodontal) disease, impacted teeth and other dental problems that may not be seen during an oral examination. The x-rays show images of the teeth and bones and help detect problems before they become serious or even before symptoms appear to the patient.
If you are a new patient, the dentist may recommend X-rays to determine the present status of your oral health and have a baseline to help identify changes that may occur later. If a previous dentist has any radiographs of you, your new dentist may ask you for copies of them. Ask both dentists to help you with forwarding your X-rays.
Common Types of X-rays
There are several types of dental x-rays, each with a different purpose. Among the most common are bitewing, periapical, full mouth series, and panoramic.
- Bitewing x-rays: can detect decay between teeth, view bone levels around the teeth, and are generally taken once a year but may be taken less often if you have a history of good oral health
- Periapical x-rays: show the roots of the teeth and the surrounding bone. They typically show more of the tooth and jawbone than the bitewing x-ray and can help diagnose specific problems such as abscesses near the root of the tooth.
- Full mouth x-rays: a group of periapical and bitewing x-rays showing all of the teeth and supporting bone. These help find complex dental problems in patients with a history of extensive dental treatment and are scheduled every 3-5 years depending on your dental health and history.
- Panoramic x-rays: show the complete upper and lower jaw and teeth on a single x-ray. These are used to see developing teeth in children and can determine if orthodontic work needs to be done. These also can show injuries to the jaw and are recommended for patients who don’t have natural teeth. These are commonly taken during an initial visit to a new dentist.
- Cone-beam Computed Tomography (CBCTs): CBCTs are 3-dimensional x-rays used by dentists to evaluate underlying bone structures, as well as soft tissue structures and nerves. They are often used when other types of dental x-rays aren’t sufficient enough for gathering information. Some procedures they are commonly used for are dental implants and root canals.
Are X-Rays Safe?
Dental X-ray exams are safe; however, they do require very low levels of radiation exposure, which makes the risk of potentially harmful effects very small. Dental x-ray tools and techniques are designed to limit the body’s exposure to radiation and every precaution is taken to ensure that radiation exposure is As Low As Reasonable Achievable (the ALARA principle). A leaded apron and/or a leaded thyroid collar may be used to shield the abdomen and thyroid.
Information Sources: https://www.mouthhealthy.org/en/az-topics/x/x-rays and Aetna’s “Dental X-Rays” Patient Information