CBCT 3D

Cone Beam Computed Tomography is capable of depicting skull bones, teeth, and soft tissues with high precision. This allows dentists and oral surgeons to plan therapy accurately and without errors. CBCT enables the identification of fine anatomical structures such as nerves, blood vessels, or sinus cavities, aiding in the preservation of these structures during surgeries. Additionally, CBCT reveals various pathological processes like periodontitis, jaw inflammations, or displaced foreign bodies, minimizing suboptimal decisions in the planning phase.

Various diseases and problems can be detected in a DVT. Changes in the jawbone in particular can be visualized very well.

There are various types of bone infections, all displaying softening and degradation of the jawbone. In X-rays, bone infections appear dark. The image illustrates a bone infection around the root tip of a broken premolar. Severe periodontitis can also lead to significant jawbone loss and jaw inflammation, as seen in the following section.

Periodontitis (inflammation of the supporting structures of the teeth) is also well-observable in CBCT. In three-dimensional imaging, there is noticeable loss of the tooth-supporting structures, resulting in decreased tooth stability. Since the jawbone is part of the tooth-supporting structures, periodontitis often accompanies jaw inflammation. The lower image displays various cross-sections of an upper molar, revealing severe periodontal bone loss with involvement of the sinus cavity.

A healthy sinus cavity is filled only with air. If the CBCT shows the sinus cavity filled, it indicates a pathological process, often caused by a diseased tooth. The image below depicts thickened sinus mucosa extending into the cavity, indicating a dentogenic (originating from the tooth) sinus infection.

Cavities are easily discernible in high-quality CBCTs taken with state-of-the-art equipment. The dentist can differentiate between enamel and dentin cavities. In the lower graphic, cross-sectional images of an upper molar reveal a dark area in the tooth crown, indicating a cavity. The distance to the tooth nerve can be measured accurately.

Foreign bodies can be located in both bone and soft tissue. These may include scattered amalgam fragments, overfilled root canal material, or broken root tips. CBCT precisely locates the position of foreign bodies, facilitating better planning for their removal in a safer and less traumatic manner. In the lower images, the exact location of a foreign body is visible in three planes.

Identifying anatomical structures is crucial before surgeries to preserve nerves or sinus cavities.

Changes in the sinus cavities can be well-diagnosed with CBCT. This information is valuable during surgeries and dental implant procedures to avoid injuring the sinus cavity. The image on the right shows a CBCT with marked sinus cavities for better anatomical understanding, highlighting the proximity of the root tips to the sinus cavity.

The inferior alveolar nerve is commonly at risk of damage during surgeries and implantations in the lower jaw. The nerve runs bilaterally in the lower jaw. Damage leads to sensory disturbances in the teeth, lower lip, and chin on the corresponding side. Arteries and veins always accompany the inferior alveolar nerve. In the images, the entry and exit points of the inferior alveolar nerve are highlighted in red.

This nerve can be damaged during implantations in the area of the middle upper incisors, causing sensory disturbances in the front palate. Similar to the lower jaw, nerves and blood vessels run together through the palate. The image depicts the course of this anatomical structure, with the exit point on the palate marked in red.

CBCT creation is straightforward. After removing metal objects like earrings, necklaces, or dentures and wearing a lead apron, the 3D X-ray image is taken. The patient sits with support for the forehead and chin, keeping the head still for a few seconds. During this brief time, the X-ray tube and sensor move around the head, creating a three-dimensional image of anatomical structures. The CBCT can be accessed within seconds, allowing the dentist to diagnose alongside the patient.

The radiation exposure in CBCT depends on parameters, the volume size of the 3D X-ray, and the CBCT device used. Therefore, it’s crucial to set the parameters correctly and choose the ideal volume size based on the individual situation. The CBCT device should be of the latest generation and high quality, as technological advancements and device quality can minimize radiation dose. Generally, the radiation exposure of CBCT is approximately ten times lower than that of a head CT scan. We use the Planmeca ProMax Mid, which features the Planmeca Ultra Low Dose protocol, allowing the creation of high-quality 3D images with minimal radiation exposure (approximately 0.021 millisieverts or mSv). To put this in perspective, the average annual radiation dose for a person in Switzerland is about 5.6 mSv.

The DVT 3D X-ray is an important diagnostic tool for complex treatment planning and prior to implantation.

Further information intended to give a better overview of the topic.