Cone Beam CT (CBCT) is an X-ray based imaging technique that, like a conventional medical CT scan, provides fast and accurate visualisation of bony anatomical structures in three dimensions. In another words, CBCT produces a 3-dimensional images of your teeth and jaws.
It is also sometimes called “Digital Volumetric Tomography” (DVT) or other alternative names.
Unlike CT-scan, CBCT scanning resolution is higher, with less artefact and scatter. The scan field of view can also be reduced to image smaller volumes and lower the radiation dose associated with each scan.
CBCT scans are useful in many different types of dentistry, especially for dental implant planning, managing impacted teeth and root canal treatments, basically to get the 3D images of the teeth and jaws. It is used by general dentists and specialists to improve diagnosis and treatment planning in the following cases:
- Size and shape of ridge, quantity and quality of bone
- Position and orientation of implants insertion
- Location of anatomic structures: mandibular canal, submandibular fossa, incisive canal, maxillary sinus
- Need for bone graft, sinus lift
- Acquire for implant planning software
Oral and maxillofacial surgery
- Orthognathic surgery planning
- Localization of impacted teeth, foreign objects
- Relationship of third molar roots to mandibular canal
- Evaluation of facial fractures and asymmetry
- Oral and maxillofacial pathology
- Localization and characterization of lesions in the jaws
- Effect of lesion on jaw in 3rd dimension: expansion, cortical erosion, bilateral symmetry
- Relationship of lesion to teeth and other structures
- Treatment planning for complex cases when 3D information needed to supplement (or substitute for) other imaging
- Patients with cleft palate
- Impacted/missing teeth
- Root angulation, root resorption
- Temporomandibular joint
- Osseous structures of TMJ
- Relationship of condyle and fossa in 3D
FAQ on CBCT
When should CBCT be used?
- Whenever information in the 3rd dimension is needed for the diagnosis, treatment planning, or management of conditions in the jaws and the maxillofacial complex.
What does the scan look like when it is done?
- The CBCT examination produces 3-dimensional pictures of the hard and soft tissue of your face. The size of the volume depends on the scanner and your particular clinical needs. The information can be viewed on a computer screen in different cross-section plane and can be rotated by the dentist to help plan treatment.
What is the difference between ordinary X-ray pictures and CBCT?
- Ordinary X-ray images (such as OPG) are 2-dimensional, flat, pictures. Your teeth and jaws are 3-dimensional, so 2-dimensional images may not give the best information.
Where do I go for a scan?
- You can come to us for CBCT scan
- or certain hospital X-ray Department in Klang Valley with CBCT unit
What are the advantages of CBCT?
- Lower radiation dose than medical CT
- Equivalent to ~1 Full mouth series of intra-oral radiographs or 6-7 panoramic radiographs
- Comfortable for patient
- Patient standing
- Only 20 second scan
- Wheelchair accessible
- Images available almost immediately on screen
- Images can be imported into other software
What will happen when I attend for the scan?
- First, you will be asked to wear a lead apron to protect your body from radiation. Next, you will be positioned carefully in a standing position. You will then be ready for the scan itself.
- The machine will move around your head in a circular motion, but will not touch you. Once the scan is finished, you will be asked to stay in the chair until the images are checked.
How long does the scan take?
- The scan itself takes only a minute or so but, in most cases, the preparation and positioning will mean that the complete scan will take about 20 minutes.
Is there anything I need to do before I come for my appointment?
- If you have earrings or other facial jewellery or piercings, these may need to be removed before the scan, so doing this in advance of your visit will save time. If you wear dentures, you will probably be asked to remove these before the scan.
Should the amount of X-rays I will receive worry me?
- No. All CBCT referrals should be justified and only carried out when it is judged that the scan is appropriate. Although the X-ray exposure with CBCT is greater than with a traditional dental X-ray examination, it is almost always much less than you would get with a “medical” CT scan that might be the only alternative.