Having a cone beam CT scan
A cone beam (CB) CT scanner uses x-rays and computer-processed x-ray information to produce 3D cross-sectional images of the jaws and teeth. It is a smaller, faster and safer version of the regular CT scanner. Through the use of a cone shaped x-ray beam, the radiation dosage is lower, and the time needed for scanning is reduced.
The machine moves around your head in a circular motion in a similar way to the panoramic dental radiography unit which is commonly used in dental surgeries and hospitals, which you may have already experienced
What happens during dental cone beam CT (CBCT)?
You will be seated in the CBCT machine. Your head will be carefully positioned and you will be asked to keep absolutely still while the scan is taken. We will ask you not to swallow, talk or move your jaw during the exposure. The positioning takes a few minutes, but each scan takes less than a minute to perform. You may need more than one scan depending on the reason for your examination. The whole procedure should not take more than 15 minutes
Why should I have a
The scan will give us detailed information which cannot be obtained from normal x-ray examinations. For example, if you are being considered for dental implants or other special procedures, it enables us to assess the exact shape of the bone
What are the risks?
CBCT scans are low-dose examinations and give an x-ray dose to the patient that is normally considerably less than a medical CT scan
A normal CT scan of the jaws at our hospital gives a radiation dose equivalent to approximately 63 to 154 days of background radiation (the x-radiation constantly present in the environment)
A CBCT scan of the jaws would be comparable to approximately 6 to 30 days of normal background radiation. So a CBCT scan of the jaws will give approximately one fifth to one tenth of the dose of a conventional CT scan of the same area
As with any x-ray examination, please inform the radiographer if you might be pregnant
Are there any alternatives?
Yes – medical CT is the alternative, but this delivers a greater radiation dose. Another alternative is not to undergo the x-ray examination at all, but without this examination it may not be possible using traditional dental x-ray pictures to assess the bone accurately enough to allow your treatment to be performed safely
- Before your CBCT you will be asked to remove glasses, dentures, hearing aids, earrings, tongue and nose studs, necklaces, hair clips and any other metal accessories that may affect the scan. This is not an examination that requires any injections or special preparations
- If you are having the scan for dental implant planning, you may be asked by your dentist to bring a localisation stent with you. This is a special ‘plate’ which you will wear rather like a denture, containing markers to guide our x-ray examination. You will only need to wear this during the scan
This procedure is not painful, but you will need to remain still for the duration of the scan. If you are claustrophobic please mention this to the radiographer so that they can offer you appropriate support and advice
- After the examination you will be able to go home straight away.
- The consultants will write a report from the scan, and it will be sent through to the dentist who has referred you to us for the examination
No special aftercare is necessary, you will be able to eat, drink and carry on all your normal activities
In the unlikely event that you experience any problems following this examination, you can contact our team during normal business hours. Outside these hours if you are worried you should go to your nearest Emergency Department (A&E)
Normally you will have a follow up appointment arranged by your dentist who referred you to us