A dental 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.
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 30 minutes.
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.
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 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.