Dental cone beam CT

There is no absolute contraindication for this test. However, CT scans are usually avoided in pregnant women, as the radiation may pose health risks for the unborn baby. Also, this test is generally avoided in children as they are highly sensitive to radiation.

A dental cone beam CT is commonly used to plan the treatment for misaligned or missing teeth. It can help the doctor in diagnosing and treating conditions such as:

• Cleft palate: A birth defect characterised by an opening in the roof of the mouth. Babies with cleft palate usually have difficulty feeding, as they cannot latch and suck properly while nursing. Read more: Cleft lip and cleft palate symptoms
• Impacted teeth: A condition when the tooth either does not erupt at all or only erupts partially from the gum. The person may show the following symptoms:
  • Bad breath
  • Tenderness or pain in gums or jaw bone
  • Bad taste when biting down on the area
  • A gap where the tooth did not erupt
  • Swelling and redness of gums near the impacted tooth
  • Prolonged headache or jaw ache
  • Difficulty opening the mouth (occasionally)
• Facial fractures (broken bones in the face): These fractures are associated with the following symptoms:
  • Pain
  • Loosened teeth
  • Bleeding
  • Bruising
  • Cuts
  • Swelling
  • Clear nasal discharge
  • Nausea or vomiting 
  • Deformity/asymmetry of the face
  • Nosebleeds
  • Numbness in the area
  • Difficulty with breathing or opening the mouth
• Tumours in jaws: A person with a jaw tumour may have persistent pain in their jaw along with swelling. Mobility of the tooth may or may not be present.
• Temporomandibular joint disorder (TMJ): This is a disorder affecting the jaw joint and muscles. It presents with:
  • Pain in the jaw joint and/or chewing muscles
  • Restricted jaw movement along with stiffness of jaw
  • Painful clicking in the jaw joint on opening or closing the mouth 

You do not need any special preparation for the dental cone-beam CT. 

However, right before the test, you will be asked to take off all metal items that may interfere with the scan, such as eyeglasses, jewellery, hair accessories and hearing aids. 

Even though removable dental work should also be removed, you must bring them with you as the doctor may need to examine them. 

Inform your doctor if you are pregnant or if there is any chance you might be pregnant.

The procedure for the scan is as follows:

• Depending on the type of CT scanner, you may either have to lie down on an exam table or sit in an exam chair. 
• You will be positioned in such a way that the area to be scanned is centred in the x-ray beam. 
• The x-ray source and detector will revolve around your head to capture images from different angles. 
• You must remain still during the imaging. 

Typically, a scan where the entire mouth and dental structures are imaged takes about 20-40 seconds, whereas a scan of a specific area takes less than 10 seconds.

No pain is felt during the scan.

The dental cone beam CT scan tells about:

• The accurate placement of dental implants (a surgical fixture placed in the jaw to support false teeth).
• In case of oral and maxillofacial surgery, it helps check for impacted teeth, facial fractures, foreign objects stuck in teeth, bone structure and tooth orientation.
• Jaw lesions (abnormal tissues) and their effect on surrounding structures.
• The condition of the bony structures in TMJ.

The benefits of this scan are:

• It is painless, accurate and non-invasive.
• The focused x-ray beam provides clear images by reducing scatter radiation.
• A single scan provides multiple views and images for a complete evaluation and precise treatment planning.
• No radiation is left in the body after the scan.
• The x-ray radiations cause no immediate side effects.

The risks of a dental cone beam CT are: 

• There is no risk as such from this test.

You can resume your routine activities after the test.

Depending on the condition to be checked for, different tests may be performed along with a dental cone beam CT, such as:

• X-ray
• Magnetic resonance imaging (MRI)
• Ultrasound
• Positron emission tomography (PET) scan or PET-CT scan
• CT scan of the face
• 3-D reconstructive scans
• Biopsy
• Endoscopy

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational point of view and is in no way a substitute for medical advice by a qualified doctor.