Cone beam computed tomography (CT) is a special type of x-ray equipment used when regular dental or facial x-rays are not sufficient.
Unlike other equipment that render images in 2- dimension, the CBCT renders images in 3 Dimension. The importance of using Cone Beam CT is illustrated by the case below.
A 19-year old boy presented with misaligned teeth (malocclusion).
Oral examination at Bellevue Dental clinic revealed absence of all four wisdom teeth.
A panoramic x-ray revealed:
- the presence of all wisdom teeth
- that the lower ones are impacted (i.e. blocked by the bone, will never erupt, and can lead to further complication). This means that they will have to be extracted.
- that the roots of the upper wisdom teeth seem to be growing in the maxillary sinus (figure 1).
Figure 1: Panoramic s-ray
Extraction of any wisdom tooth often requires the extraction of the opposite one. As this applies to this patient, all his wisdom teeth will need to be extracted before any orthodontic intervention (braces placement). In addition, a surgical procedure is required for the extraction and there is need to be extremely careful given the position of the root with regards to the sinus. To obtain a more accurate image of the situation, a Cone Beam CT x-ray providing a 3D image is required.
The CBCT x-ray (figure 2) revealed:
- The roots of the lower wisdom teeth do not touch the mandibular nerve,
- The roots of the upper wisdom teeth are quite near the maxillary sinus but are not in contact with the sinus (figure 3).
With this new set of information, the dental surgeon at Bellevue Dental clinic is better prepared to undertake the wisdom teeth extraction.
Figure 2: CBCT x-ray
Figure 3: An isolated view of a Cone beam CT Scan