Sometimes dental X-rays alone do not produce a sufficiently detailed image for us to diagnose your oral health issue. Computed tomography would produce a more detailed image, but a traditional medical CT scan would expose you to significant amounts of radiation, which could increase your cancer risk. Instead, we perform a cone beam CT scan, also known as a CBCT scan.
A cone beam scan exposes you to less radiation than a medical CT would while producing the detailed images we need to diagnose and treat your dental condition.
How Does a CBCT Scan Compare to Other Imaging Techniques?
Computed tomography is a type of X-ray that focuses the beam precisely and then uses a computer to combine the data collected into a useful image. The image quality is much better than that achieved with a traditional dental X-ray because the beam’s focus results in less scatter radiation.
A cone beam CT scan is different from a medical CT because it uses a cone-shaped beam to focus very precisely on the mouth. The computer then produces a three-dimensional image of the teeth, bones, soft tissues, and nerve pathways. In addition to exposing patients to a relatively lower dose of radiation compared to a traditional CT, a cone beam scan also uses more compact equipment. We can perform your CBCT scan right in our office.
What Are the Risks of a Cone Beam CT Scan?
Although the cone beam scan exposes patients to less radiation than a medical CT, it involves more radiation than a traditional dental X-ray. Therefore, it is not used on a routine basis but only when the condition requires more detailed imaging than a traditional X-ray can produce. If there is a possibility that you could be pregnant, it is important for you to inform us before your cone beam CT scan. Depending on the situation, we may defer the scan until after the baby’s birth or modify the CBCT scan technique to produce less radiation.
The risks associated with performing a cone beam scan are greater for young children because they have a greater sensitivity to radiation. We will only perform a cone beam CT scan on a pediatric patient using a low-dose technique, and then only when it is absolutely necessary.
What Are the Benefits of a Cone Beam Scan?
For most patients, the risks from a cone beam CT scan are very small, and the benefits far outweigh them. It is used for treatments that require more precise planning, for which it is useful because it provides more information than a traditional dental X-ray. For example, a single scan can produce images of both soft tissue and bone at the same time.
In addition to the accuracy of the images produced by a cone beam scan, it is also noninvasive and causes no pain and no immediate side effects. A cone beam CT scan is also more versatile because of the ability to manipulate the wide variety of angles and views produced by a single scan to make the evaluation more complete.
When Is a CBCT Scan Used?
Sometimes the origin of oral pathology or pain is not apparent from a dental examination and traditional X-rays. A cone beam scan is useful for diagnosing dental abnormalities that may result from trauma, endodontic infection, and severe dental caries (i.e., tooth decay). It is also often used to aid in surgical planning for the placement of dental implants, reconstructive surgery, or the removal of impacted teeth.
A cone beam CT scan can also be used to evaluate the jaw. For example, sometimes tumors of the jawbone occur, and a cone beam scan can be useful for detecting and measuring them, as well as treating them.
A cone beam scan can also be used to evaluate structures outside the mouth, such as the nasal cavity and sinuses. A cleft palate is a congenital facial defect in which the bones of the upper jaw/nasal floor do not come together properly while the unborn baby is developing in the womb. It is correctable with surgery, and a cone beam CT scan may be used prior to assess the extent of the defect. Cone beam scans have also been used to assess sleep disorders involving abnormalities of the airway.
What Happens During a Cone Beam CT Scan?
Depending on the type of equipment used, a cone beam scan requires you to either lie down on an exam table or sit in an exam chair. We will position you so that the beam is centered upon the area of interest. It is important that you stay very still while the scan is in progress, which includes refraining from talking or swallowing, or the images produced may not be usable.
The X-ray source and detector will revolve around you in a 360-degree rotation. If the CBCT scan is focusing on a specific area, the scan will take less than 10 seconds. If the whole mouth is to be imaged, however, the complete scan takes between 20 to 40 seconds.
Although the scan is over in less than a minute, during that time it can produce between 150 and 200 two-dimensional X-ray images in high resolution. The computer then combines these digitally to produce a 3-D image of the area of concern. The information that we receive from this 3-D image is invaluable to us in evaluating your condition and presenting you with appropriate treatment options.
Once we have the results of your scan, we will either communicate them to your referring dentist or physician or discuss them with you directly.
How Do You Prepare for the Procedure?
Rarely, we may find it necessary to administer imaging contrast before your CBCT exam. The contrast is a special liquid that we inject into your body to enhance the images produced by the scan. Abnormal tissues, such as malignant tumors, take up the contrast and allow us to visualize it more clearly. However, most cone beam scans take place without any contrast.
Because a cone beam CT scan involves taking X-rays, we ask you to leave any metal accessories, such as jewelry, at home. If you wear eyeglasses or dentures, we will ask you to remove them before the scan takes place to avoid disruption. You can put them back in place once the cone beam scan is complete.
We may ask you to wear a gown during your cone beam CT scan. Otherwise, you should wear clothing that is loose-fitting and comfortable enough for you to sit still for the required duration. Other than that, there is typically little tono preparation required prior to your CBCT scan.
What Are the Short-Term and Long-Term Side Effects of a Cone Beam Scan?
There are no short-term side effects of a cone beam CT scan. You will experience no pain during the scan and be able to return to your normal activities as soon as your appointment is over. Because of the exposure to radiation, there is a potential risk of developing cancer in the long-term as a result of a cone beam scan, but this is believed to be very small.
We will take every reasonable precaution to expose you to no more than the necessary dose of radiation and prevent any long-term adverse effects. Contact us to find out more about our CBCT scan capabilities at Summit OMS.