CBCT

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Recently, owing to its reliability and accuracy, CBCT has also been used to evaluate the canal preparation in different instrumentation techniques.[75–76]

Implantology

With increased demand for replacing missing teeth with dental implants, accurate measurements are needed to avoid damage to vital structures. This was achievable with conventional CT. However, with CBCT giving more accurate measurements at lower dosages, it is the preferred option in implant dentistry today (Figs. 4a & b).[2,6,11,18,70,77–89]

With new software that constructs surgical guides, damage is also reduced further.[77,84,90–93] Heiland et al.94 describe a technique in which CBCT was used inter-operatively in two cases to navigate the implant insertion following microsurgical bone transfer.

CBCT enables the assessment of bone quality and bone quantity.[18,26,70,80–81,85,88,95–97] This leads to reduced implant failure, as case selection can be based on much more reliable information. This advantage is also used for post-treatment evaluation and to assess the success of bone grafts (Figs. 5a–d).[18,88]

Orthodontics

Orthodontists can use CBCT images in orthodontic assessment and cephalometric analysis.[6,70,84,98–99] Today, CBCT is already the tool of choice in the assessment of facial growth, age, airway function and disturbances in tooth eruption.[100–103] CBCT is a reliable tool in the assessment of the proximity to vital structures that may interfere with orthodontic treatment.[104–105] In cases in which mini-screw implants are placed to serve as a temporary anchorage, CBCT is useful for ensuring a safe insertion[106–108] and to assess the bone density before, during and after treatment (Fig. 6).[109–110]

Having different views in one scan, such as frontal, right and left lateral, 45-degree views and sub-mental, also adds to the advantages of CBCT.[111,124] As the images are self-corrected from the magnification to produce orthogonal images with 1:1 ratio, higher accuracy is ensured. CBCT is thus considered a better option for the clinician.[113]

Temporomandibular joint disorder

One of the major advantages of CBCT is its ability to define the true position of the condyle in the fossa, which often reveals possible dislocation of the disk in the joint, and the extent of translation of the condyle in the fossa.[18,56,114] With its accuracy, measurements of the roof of the glenoid fossa can be done easily.[115–116] Another advantage of some of the available devices is their ability to visualise soft tissue around the TMJ, which may reduce the need for magnetic resonance imaging in these cases.[117]

Owing to these advantages, CBCT is the imaging device of choice in cases of trauma, pain, dysfunction, fibro-osseous ankylosis and in detecting condylar cortical erosion and cysts.[70,87,118–120] With the use of the 3-D features, the image-guided puncture technique, which is a treatment modality for TMJ disk adhesion, can safely be performed.[121]

Periodontics

CBCT can be used in assessing a detailed morphologic description of the bone because it has proved to be accurate with only minimal error margins.] The measurements proved to be as accurate as direct measurements with a periodontal probe.[56,123] Furthermore, it also aids in assessing furcation involvements]

CBCT can be used to detect buccal and lingual defects, which was previously not possible with conventional 2-D radiographs.[] Additionally, owing to the high accuracy of CBCT measurements, intra-bony defects can accurately be measured and dehiscence, fenestration defects and periodontal cysts assessed.[ CBCT has also proved its superiority in evaluating the outcome of regenerative periodontal therapy.[]

General dentistry

Based on the available literature, CBCT is not justified for use in detecting occlusal caries, since the dose is much higher than conventional radiographs with no additional information gained. However, it proved to be useful in assessing proximal caries and its depth.[20] Table II shows examples of typical doses of various dental radiological procedures in dental practice.

Forensic dentistry

Many dental age estimation methods, which are a key element in forensic science, are described in the literature. CBCT was established as a non-invasive method to estimate the age of a person based on the pulp–tooth ratio.[]

Discussion

CBCT scanners represent a great advance in dento-maxillofacial (DMF) imaging. This technology, introduced into dental use in the late 1990s,[] has advanced dentistry significantly. The number of CBCT-related papers published each year has increased tremendously in the last years. The above systematic review of the lite­rature related to CBCT-imaging applications in dental practice was undertaken in order to summarise concisely the indications of this new image technique in different dental specialties.

Cone-beam computed tomography in dentistry was used as key phrase in this systemic review. Other terminology encountered in the literature, such as cone-beam volumetric scanning, volumetric computed tomography, dental CT, dental 3-D CT and cone-beam volumetric imaging, did not result in additional relevant papers.[]

The clinical applications for CBCT imaging in dentistry are increasing. The results of this review demonstrate that 134 papers were clinically relevant and that the most common clinical applications are in the field of oral and maxillofacial surgery, implant dentistry, and endodontics. CBCT has limited use in operative dentistry owing to the high radiation dose required in relation to its diagnostic value.