what are dental xrays

What Are Dental X Rays

what are dental xraysSummerlin, Las Vegas, and Henderson Nevada


Dental X-rays are pictures of the teeth, bones, and soft tissues around them to help find problems with the teeth, mouth, and jaw. X-ray pictures can show cavities, hidden dental structures (such as wisdom teeth), and bone loss that cannot be seen during a visual examination. Dental X-rays may also be done as follow-up after dental treatments.

The following types of dental X-rays are commonly used. The X-rays use small amounts of radiation.

  • Bitewing X-rays show the upper and lower back teeth and how the teeth touch each other in a single view. These X-rays are used to check for decay between the teeth and to show how well the upper and lower teeth line up. They also show bone loss when severe gum disease or a dental infection is present.
  • Periapical X-rays show the entire tooth, from the exposed crown to the end of the root and the bones that support the tooth. These X-rays are used to find dental problems below the gum line or in the jaw, such as impacted teeth, abscesses, cysts, tumors, and bone changes linked to some diseases.
  • Occlusal X-rays show the roof or floor of the mouth and are used to find extra teeth, teeth that have not yet broken through the gums, jaw fractures, a cleft in the roof of the mouth (cleft palate), cysts, abscesses, or growths. Occlusal X-rays may also be sued to find a foreign object.
  • Panoramic X-rays show a broad view of the jaws, teeth, sinuses, nasal area, and temporomandibular (jaw) joints. These X-rays do not find cavities. These X-rays DO show problems such as impacted teeth, bone abnormalities, cysts, solid growths (tumors), infections and fractures.
  •  Digital X-rays can be sent to a computer to be recorded and saved.

A full-mouth series of periapical X-rays (about 14 – 21 X-ray films) is most often done during a person’s first visit to the dentist. Bitewing X-rays are used during checkups to look for tooth decay. Panoramic X-rays may be sued occasionally. Dental X-rays are scheduled when you need them based on your age, the risk for disease, and signs of disease.

What is a Panoramic Dental X-ray? 

Panoramic radiography, also called panoramic X-ray, is a two-dimensional (D-D) dental X-ray that captures the entire mouth in a single image, including the teeth, upper and lower jaws, surrounding structures and tissues.

The jaw is a curved structure similar to that of a horseshoe. However, the panoramic X-ray produces a flat image of the curved structure. It is typically set to provide details of the bones and teeth.

Unlike a traditional intraoral X-ray where the film is placed inside of the mouth, the film for a panoramic X-ray is contained inside of the machine.

What are some common uses of this procedure?

A panoramic X-ray is commonly performed by dentists and oral surgeons in everyday practice and is an important diagnostic tool. It covers a wider area than a conventional intraoral X-ray and, as a result, provides valuable information about the nasal area, maxillary sinuses, tooth position and gum and bone irregularities. This image is also used to plan treatment for full and partial dentures, braces, extractions, and implants.

A panoramic X-ray can also reveal the presence of an existing issue or potential problem such as: 

  • Advanced periodontal disease
  • Oral cysts
  • Tumors and oral cancer
  • Impacted teeth
  • Temporomandibular joint disorder (TMJ)
  • Sinusitis

How should I prepare?

A panoramic X-ray requires no special preparation.

You will be asked to wear a lead apron as a safety prevention to protect the rest of your body from any radiation exposure that may scatter from the panoramic X-ray beam. You may also be asked to remove your jewelry from the region being imaged, eyeglasses and any metal objects that might interfere with the X-ray images.

Women should always inform their dentist or oral surgeon if there is any possibility that they are pregnant. Many imaging tests are not performed during pregnancy so as not to expose the fetus to radiation. If an X-ray is necessary, the precautions will be taken to minimize the radiation exposure to the baby.

What does the equipment look like?

A panoramic x-ray machine consists of an X-ray tube mounted on a horizontal arm. X-ray film or a detector are mounted on another horizontal arm on the opposite side of the patient. For a sharper, clearer image, the patient’s head is positioned with chin, forehead and side rests. The patient is also provided with a bite block to prop open the oral cavity.

How does the procedure work?

X-rays are a form of radiation like light or radio waves. X-rays pass through most objects, including the body. Once it is carefully aimed at the part of the body being examined, an X-ray machine produces a small burst of radiation that passes through the body, recording an image on photographic film or a special detector.

During a panoramic X-ray, the X-ray tube rotates in a semicircle around the patient’s head, starting at one side of the jaw and ending at the other side.

Rather than relying on film placed inside the mouth, a panoramic X-ray machine projects a beam through the patient onto film or a detector rotating opposite the X-ray tube.

Until recently, X-ray images were maintained as a hard film copy (much like photographic negative). Today, most images are digital files that are stored electronically. These stored images are easily accessible and are frequently compared to current X-ray images for diagnosis and disease management.

The digital format also allows the dentist to adjust and change the contrast, brightness and darkness of the image for better visualization of certain structures and tissues. Images on film cannot be adjusted or changed.

How is the procedure performed?

This examination is usually done on an outpatient basis.

First, you will be situated in the center of the unit where the technician will carefully position and secure your head. The unit can be adjusted to accommodate a patient standing or sitting in a wheelchair

A bite block is then placed in your mouth to ensure proper alignment of the teeth. Correct placement of the teeth and the head is important for obtaining a clear image.

You will be asked to remain very will while the rotating arm travels in a semicircle around the perimeter of your head and the images are being recorded, which can typically take between 12 to 20 seconds.

What will I experience during and after the procedure?

A panoramic X-ray is painless, fast and easy and may be recommended over intraoral X-rays for patients that have a sensitive gag reflex.

What are the benefits vs. risks?


  • No radiation remains in a patient’s body after an X-ray.
  • X-rays usually have no side effects in the typical diagnostic range for this exam.
  • Panoramic X-rays can be used for very young children since the film does not have to be placed inside the mouth.


  • Women should always inform their dentist or oral surgeon if there is any possibility that they are pregnant.

What are the limitations of the Panoramic X-ray?

A panoramic X-ray does not provide precise and detailed information about each individual tooth or soft tissues, such as the muscles. It is generally used as an initial evaluation of the bones and teeth. If further evaluation is needed, a computed tomography (CT) scan or magnetic resonance imaging (MRI) may be ordered. Frequently, there is also a degree of distortion on the panoramic X-ray; therefore it may be difficult to obtain accurate measurements.