Why Does My Dentist Take X-Rays?

There are different types of x-rays (also known as radiographs) that we take to help us diagnose different dental conditions. In this blog post, we will review different types of x-rays and why we take each type.

Types of Radiographs

  1. Bitewing
  2. Periapical
  3. Panoramic
  4. Cone Beam (CBCT)

bitewing x ray

Bitewing X-Ray

The first and most basic type of radiograph that your dentist takes is a bitewing radiograph. Bitewings are principally used to check for cavities between posterior teeth. Although we check teeth for cavities during our clinical exam, our eyes cannot see between the teeth, therefore we use bitewing radiographs to help us diagnose decay. Bitewing radiographs are taken once per year during cleaning appointments to check for cavities.


Periapical x-ray

Periapical X-Ray

A periapical radiograph, sometimes simply referred to as a “PA,” is used to help us see the roots of our teeth. Since the roots of our teeth are hidden below the gums, it is not possible to visualize them during a clinical exam. Additionally, periapical radiographs can be used to detect cavities on front teeth.


Cone Beam Computed Tomography (CBCT)

A CBCT is the only three-dimensional radiograph on the list. While bitewings, periapicals, and panoramic radiographs are all two-dimensional radiographs, a CBCT provides a 3D image of a particular area that is highly accurate. A CBCT can be for an area as large as the entire mouth, or as small as a few teeth. CBCTs are especially useful when planning for dental implants or checking for the proximity of adjacent anatomical structures in three dimensions. Check out this Youtube video explaining what a CBCT is:

Other uses for Radiographs:

  • Monitor Bone Loss
  • Check for Pathology (growth, tumor, ectopic tooth, etc)
  • Check if a Crown is fitting correctly
  • See if something is stuck between teeth
  • Root Canal procedures
  • To check for presence of an infection

This is a simple overview of the different types of dental radiographs and what they are used for. There are other types of x-rays that your dentist may take as well as different reasons for taking them, but that is beyond the scope of this blog post. The frequency and type of radiographs taken are tailored to the individual patient. Your dentist will decide which, if any, x-rays are appropriate for you.

Keep watch for our next blog post!

Teach Me About Teeth And Cavities!

Teeth have multiple components to them. There is an outer enamel layer, an inner dentin layer and a nerve that runs through the very center of the tooth.

Healthy Tooth Anatomy

How Are Cavities Formed

A cavity forms when acid from the bacteria in your mouth eat away at the enamel and dentin layers of the tooth. The acid makes a hole in the tooth by eating away tooth structure (enamel and dentin), which allows bacteria to get inside. If a cavity gets too big, it can travel beyond the enamel and dentin layers and start eating away at the nerve of the tooth. Cavities that have reached the nerve of the tooth can be responsible for shooting, throbbing dental pain that keeps you up at night. Read more