- CBCT offers decreased irradiation dose vs spiral CT scan
- Radiation dose dependent on mA and exposure time; not on voxel size
- Dimensional accuracy has been proven to be high
- Different hardwares offer variety of fields of view (such as 4 x 4 to 15 x 20 cm) according to the clinical indication
- Both 2D and 3D images can be obtained
- Hounsfield unit measurements not as reliable as on spiral CT
- Integrating a planned or existing prosthetic device in the images is unvaluable for treatment planning
- Radiation source collimated at its source and then diverges into a fan shape to reach detectors. This results in a cone beam.
- Pixel (picture + element) is the smallest single component of a 2-D image, whereas a voxel is the smallest element in 3-D environment.
- Large fields of view (FOV) visualize both jaws and their relationship.
- Small FOVs offer detailed images of bone trabeculae and cortex.
- Grayscale values vary for specific tissues within the image and are not as reliable as in spiral CT.
- CBCT can detect clinically relevant structures which are not visible on panoramic/intra-oral radiographs, such as the incisor canal, lingual concavities and missing osseous cortex
- CBCT 2-D image, showing the mesial extension of the incisor canal
- The CBCT is essential for preoperative planning and CAD-CAM manufacturing of drill guides and/or prostheses
- Except for gray values, CBCT provides information as accurately or even better as spiral CT, with less radiation exposure and costs
Fig 2: NobelClinician software screenshot - a CBCT is essential for preoperative planning and CAD-CAM manufacturing of drill guides and/or prostheses.