3D Diagnostics

What is 3D diagnostics (CBCT)?

Cone-beam computed tomography (CBCT) is an X-ray method that captures a three-dimensional volume of the jaws, teeth, sinuses and jaw joint in a single rotation. A conventional X-ray compresses structures into one plane; CBCT lets the dentist measure height, width and depth in any slice. In the clinic CBCT is not a routine examination — it is an indication-based service that answers a specific clinical question in implant, endodontic, surgical and orthodontic planning.

When is it used?

The general rule: not “3D for every patient”, but 3D when 2D cannot answer the question.

• Implant planning — bone height and width, distance to the nerve canal and sinus (the 2012 AAOMR position recommends cross-sectional imaging)
• Endodontics — complex canal anatomy, a persistent periapical lesion, suspected root fracture, retreatment planning
• Wisdom teeth — the root's relationship to the nerve canal when the panoramic X-ray shows risk signs
• Cysts, tumours and bone pathology — size, borders, neighbouring structures
• Jaw joint — bony changes of the condyle, trauma
• Orthodontics — impacted teeth, suspected root resorption, skeletal asymmetry (AAOMR 2013: not routine, on indication)
• Sinus — odontogenic sinusitis and sinus-lift planning

Its role in implant planning

The implant's length, diameter and angle are chosen from the real bone dimensions; the safety distance to the nerve canal in the lower jaw and to the sinus in the upper jaw is measured on the slices. According to a systematic review (2014) and the AAOMR position, cross-sectional imaging of the implant site is the standard recommendation; CBCT data is merged with the intraoral scan and the design of the future tooth to produce the digital plan and, where needed, a surgical guide. Bone deficiency (the need for grafting or a sinus lift) is identified here as well.

Its role in endodontics

According to the AAE/AAOMR joint position statement (2015), CBCT is not routine in root canal treatment; a limited (small-FOV) scan is indicated for complex anatomy, an unlocated canal, persistent symptoms, suspected root fracture or resorption and surgical endodontic planning. A 2026 meta-analysis confirms that CBCT detects periapical lesions significantly more often than 2D radiographs — but not every detected change needs treatment; the decision is made together with the clinical picture.

Its role for wisdom teeth

The first step in assessing a wisdom tooth is a panoramic X-ray. When risk signs are present — the root overlapping the nerve canal, darkening or narrowing of the canal — CBCT shows the root's position relative to the canal (buccal/lingual, contact) and can change the surgical plan. Without risk signs CBCT is usually not needed.

Its role in jaw-joint disorders

Most jaw-joint complaints are diagnosed clinically. CBCT is used on indication to show the bony components — condyle shape, cortical bone, degenerative changes, trauma; according to a systematic review (2024) it is highly accurate for detecting bony changes, while MRI is preferred for the disc and soft tissues.

Its role in orthodontics

According to the 2013 AAOMR recommendations, CBCT is not a routine orthodontic record; it is indicated for impacted and abnormally positioned teeth, suspected root resorption, clefts and skeletal asymmetry and mini-screw planning — with the smallest appropriate FOV. Panoramic and cephalometric X-rays remain the standard orthodontic records.

What is FOV?

FOV (field of view) is the scanned volume. A small FOV (a few teeth, for example for root canal treatment) gives higher resolution and a lower dose; a medium FOV covers one jaw, a large FOV both jaws, the sinuses and the joints. Dose and interpretation burden increase with FOV, so the dentist chooses the smallest field that covers the clinical question — the practical application of the ALADA principle (“as low as diagnostically acceptable”).

How is the scan performed?

1. 1

   Indication and registration

   The treating dentist defines the clinical question and the region needed; pregnancy, previous images and metal objects are asked about.

2. 2

   Preparation

   Earrings, necklaces, glasses and removable dentures are taken off; a protective apron is put on.

3. 3

   Positioning

   The chin is placed on the rest, the head is stabilised, and the correct plane is set with light guides.

4. 4

   FOV and protocol selection

   According to the indication, the smallest appropriate field of view, voxel size and dose mode (child/adult) are selected.

5. 5

   Scan

   The unit makes one rotation around the head; exposure lasts 10–35 seconds; you need to stay still, there is no pain.

6. 6

   Reconstruction

   The software converts the volume into 3D voxels; the DICOM file and slices are ready in a few minutes.

7. 7

   Clinician interpretation and plan

   The image is interpreted together with the clinical data; measurements and findings go into the treatment plan and are explained to the patient on screen.

How long does the scan take?

The exposure itself is 10–35 seconds and the total time in the room about 3–5 minutes; the DICOM file and initial images are given at the same visit, and the dentist's written interpretation is usually ready the same day. A stage-by-stage timeline is in the blog article.

Radiation dose

The dose is not a universal number — it depends on the field of view, the device and the protocol. According to a 2015 meta-analysis, the effective dose of dental CBCT averages ~34 μSv for a small FOV, ~88 μSv for a medium and ~131 μSv for a large one; for comparison, a panoramic X-ray is a few tens of μSv and a medical head CT usually 1–2 mSv. Children are more radiosensitive, so a paediatric mode and a small FOV matter. The clinic's approach is indication-based: the scan is ordered only when a question could change the outcome, the smallest appropriate FOV is selected, and an existing recent image is not repeated. The phrases “completely safe” or “needed for everyone” are not used — benefit and risk are assessed for each patient individually.

CBCT versus medical CT

CBCT collects the volume in one rotation with a cone beam and a flat-panel detector and gives high resolution for bone and teeth; medical CT (MSCT) is superior in soft-tissue contrast and density measurement, and its dose is usually higher. For questions about teeth and jawbone the clinic chooses CBCT; for tumours, spread of infection into soft tissue or questions about the joint disc the patient is referred for medical CT/MRI.

How are the results used?

A CBCT image is data, not a “report”: the treating dentist interprets it together with the complaint, the examination and other X-rays. In implant planning the measurements become the digital design, in endodontics a canal map, in surgery an access plan. Systematic reviews show that incidental findings on CBCT (sinus changes, bone islands, impacted teeth) are common — not all are disease, but they are recorded and a radiologist's report is obtained when needed. The DICOM file is given to the patient.

Risks and limitations

• Radiation — low, but not zero; a scan without indication is not justified
• Soft tissue — limited contrast; MRI/CT for the disc, muscles and mucosa
• Metal artefacts — image quality can drop around crowns, implants and fillings
• Motion artefacts — in children and anxious patients
• Incidental findings — require additional interpretation and sometimes further investigation
• Over-diagnosis — not every detected change needs treatment
• Density measurement — CBCT does not provide reliable Hounsfield units

Price

The prices below come from the same source as the site's Prices section. CBCT can be taken as part of treatment (implant, endodontic or surgical planning) or separately on referral from another dentist; in either case the patient receives the DICOM file and the images.

Doctor and clinic

At Smile by Dr. Bakhtiyar (Baku, Babek Avenue 1131) the indication for CBCT and its interpretation are decided by the treating dentist; implant and surgical planning is led by Dr. Bakhtiyar Aliyev, orthodontic and jaw-joint questions by Dr. Maharram Mammadov. The image forms the basis of the clinic's digital planning workflow — intraoral scan, design, surgical guide.