Key takeaways
- Field of view (FOV) is the most important CBCT choice. Small FOVs suit endodontics and single implant sites, medium FOVs cover one or both arches, and large FOVs cover the skull, airway, and TMJs for ortho and surgery.
- Smaller voxels mean finer detail but usually more dose and noise. Pick the largest voxel and smallest FOV that answer the clinical question.
- The ADA's 2024 radiation safety report says CBCT should not be used routinely or as first-line imaging when lower-dose imaging would answer the question, and calls for the smallest FOV necessary.
- The 2026 ADA and AAOMR recommendations say the whole volume should be examined, not just the region of interest, and complex findings may warrant referral to an oral and maxillofacial radiologist.
- Most states require registration, and many require a shielding plan and physicist testing. Plan the room and the paperwork before the purchase order.
Cone beam computed tomography (CBCT) gives dentists three-dimensional images of the jaws and teeth. It has become standard in implant planning, common in endodontics and oral surgery, and increasingly present in general practices. It also delivers more radiation than conventional dental x-rays, and it captures anatomy far beyond the teeth. This guide covers how CBCT works, how to match the unit to your practice, daily operation, dose optimization, maintenance, troubleshooting, and the compliance picture. For buying a secondhand unit, read our used CBCT buying guide, which covers licensing, inspection, and installed cost in depth.
What a CBCT unit does and how it works
A CBCT unit rotates an x-ray source and a flat panel detector around the patient's head, usually in a single sweep. The beam is shaped like a cone (or a pyramid), so each exposure captures a two-dimensional projection of a volume rather than a thin slice. The unit collects hundreds of these projections during the rotation, and reconstruction software turns them into a 3D volume made of voxels, the 3D equivalent of pixels. Clinicians then scroll through slices in any plane, build panoramic-style reformats, trace nerve canals, and plan implants.
The FDA regulates dental CBCT systems as computed tomography x-ray systems under 21 CFR 892.1750, through both its medical device and radiation-emitting product authority. Its dental CBCT page notes that CBCT delivers less radiation than conventional medical CT but typically more than conventional dental x-ray exams, and that the concern is greater for children.
Parts you should know
- X-ray tube and generator: the source. Tube life is consumed by exposures.
- Flat panel detector: the most expensive single component, sensitive to calibration and handling.
- Gantry and rotating arm: the moving assembly; many units also take pans, and some take ceph images.
- Patient positioning system: chin rest, bite block, head supports, and positioning lights; some units scan seated patients.
- Acquisition and reconstruction workstation: computing hardware that must meet the manufacturer's specifications.
- Viewing and planning software: often licensed separately by seat or module.
- QA phantom: a test object used for the manufacturer's image quality checks.
Which type does your practice need?
Field of view by use case
FOV is usually described as diameter by height in centimeters. Exact sizes vary by model, many units offer several FOVs, and published cutoffs between small, medium, and large differ from source to source. The categories below are general.
| FOV class | Typical coverage | Common uses | Considerations |
|---|---|---|---|
| Small (roughly 5 cm or less) | A few teeth or a sextant | Endodontics (canal anatomy, fractures, periapical lesions), single implant sites, impacted teeth | Usually the finest resolution and lowest dose per scan; not enough for full-arch planning |
| Medium (roughly 5 to 10 cm) | One arch or both arches | Multiple implants, third molars, general 3D diagnostics, guided surgery | The common general-practice choice; the sinus and parts of the airway may be included |
| Large (roughly 10 cm and up) | Both jaws plus skull base, airway, TMJs | Orthodontics, orthognathic surgery, airway assessment, full-arch reconstruction, trauma | Higher dose per scan and far more anatomy to interpret; often paired with a ceph arm |
Many combination units let you switch between FOVs, and some models can be upgraded to a larger FOV by license or hardware change. Ask what the upgrade costs before buying a small-FOV unit with larger plans in mind.
Voxel size and resolution
Voxel size is the edge length of each cube in the volume, typically ranging from well under 0.1 mm for high-resolution endodontic protocols to around 0.3 to 0.4 mm for large-volume surveys. Smaller voxels show finer detail (a thin fracture line or an extra canal) but usually require more exposure to keep noise acceptable, and they create larger files. Larger voxels are adequate for many implant and ortho questions. Voxel size alone does not guarantee sharpness; detector quality, motion, and reconstruction all matter.
A decision guide
- Endodontic practice: small FOV with high-resolution protocols.
- General practice placing implants: medium FOV covering both arches, with a small-FOV option for single sites and endo questions.
- Oral surgery and multi-specialty group: medium to large FOV, possibly with ceph.
- Orthodontics: large FOV, often with a ceph arm, and low-dose protocols for younger patients.
- Low 3D volume: if you would scan a few patients a month, referral to an imaging center or specialist may be cheaper than owning a unit and its compliance program.
Space, shielding, and infrastructure
Confirm the footprint, rotation clearance, ceiling height, wall or floor mounting, wheelchair access, dedicated electrical circuit, and network cabling to the workstation. Many states require a shielding plan by a qualified expert before installation, and the plan depends on your workload, the unit, and who occupies the adjacent spaces. Do the shielding plan before construction. See operatory buildout and design and equipment planning.
How to use it: daily operation
These steps are generic. Follow your unit's instructions for use (IFU), your state rules, and your written radiation safety procedures. Operators must meet your state's credential requirements for CBCT, which may differ from those for intraoral or pan imaging.
Start of day
- Power on the unit and workstation in the order the IFU specifies, and let the unit finish its self-test and any warm-up.
- Run any daily QA check the manufacturer or your state program requires, and record the result.
- Confirm that positioning lights work, accessories are present and clean, and there are no error codes.
- Check free space on the workstation and that yesterday's backups completed. Volumes are large.
For each patient
- Confirm the dentist's order specifies the clinical question, the region, and the FOV. CBCT is ordered on clinical need; the 2026 recommendations state it is not indicated for caries detection.
- Have the patient remove metal objects, eyeglasses, removable appliances, and jewelry in the field.
- Select the smallest FOV and the protocol (resolution and dose level) that answers the question. Use pediatric or low-dose protocols where the manufacturer offers them and the question allows.
- Position with the bite block, chin rest, and head supports, centering the region of interest with the positioning lights. Stabilization matters more in CBCT than in 2D because motion degrades the whole volume.
- Explain the scan length and ask the patient to stay completely still and not swallow if possible.
- Take a scout image if the unit offers one, confirm the region is inside the FOV, then expose from your protected position.
- Review the reconstruction for motion and coverage before the patient leaves.
Between patients and end of day
- Replace bite block covers and disinfect chin rests, head supports, and handles with approved products.
- Archive volumes per your retention policy and confirm backups.
- Shut down per the IFU and log any errors, retakes, or motion rescans.
Dose optimization and interpretation
Keeping dose appropriate
The ADA's 2024 expert panel report on radiation safety says CBCT should not be used routinely, should not be first-line imaging when lower-dose options are adequate, and should use the smallest FOV necessary for the anatomy of interest. It also recommends that CBCT units be evaluated by a qualified expert at least every two years, and preferably annually. In practice:
- Justify every scan. Document the clinical question before exposure.
- Collimate. The smallest FOV that covers the question.
- Match resolution to the question. Use high-resolution protocols for fine endodontic detail and standard or low-dose protocols for implant and ortho surveys where they suffice. Manufacturers such as Planmeca market ultra-low-dose protocols intended for cases where high resolution is not needed.
- Protect children. Use pediatric protocols and size settings.
- Avoid retakes. Good positioning and stabilization save a second scan.
- Do not use thyroid collars routinely. The 2024 report says thyroid and abdominal shielding are no longer recommended in dental imaging, including CBCT. Follow your state's rule if it differs.
Who reads the whole volume
A CBCT volume captures everything within the FOV: sinuses, airway, cervical spine, skull base, and soft tissue calcifications. The 2026 ADA and AAOMR recommendations state that the entire image or volume should be examined for findings, not just the area of interest, and that complex cases may warrant referral to an oral and maxillofacial radiologist. Larger FOVs carry more incidental anatomy and a larger reading burden. Decide before purchase whether your dentists will read volumes themselves, send some or all to a radiologist, or both, and discuss the professional liability side with your malpractice carrier. See malpractice insurance for dentists.
Guidance in this area has been evolving. The 2026 ADA and AAOMR patient selection recommendations are the first ADA guidance to address both 2D and CBCT imaging in specific clinical scenarios. Check the ADA's x-ray topic page for the current documents before writing office protocols.
Maintenance schedule
| Task | Frequency | Who | Notes |
|---|---|---|---|
| Replace bite block covers; disinfect contact points | Every patient | Clinical staff | Chin rest, head supports, handles |
| Self-test review and error log check | Daily | Clinical staff | Record codes and dates |
| Workstation storage and backup check | Daily or weekly | Office manager or IT | Volumes fill drives quickly; test restores periodically |
| Manufacturer QA phantom test | Per manufacturer and state program (often monthly or quarterly) | Trained staff | Keep results; trending catches detector drift |
| Positioning and motion rescan review | Monthly | Dentist and lead operator | Retraining target list |
| Software, firmware, and workstation updates | As released, after compatibility check | IT with the dealer | Check supported operating systems before updating |
| Preventive maintenance and detector calibration | Per manufacturer, often annually | Factory-trained technician | Also after any relocation |
| Qualified expert evaluation | At installation, then per state rules | Medical or health physicist, or state-recognized provider | ADA panel: at least every two years, preferably annually |
| Shielding review | When workload, unit, or adjacent room use changes | Qualified expert | Keep the shielding report permanently |
Troubleshooting
Staff can address positioning, protocol selection, patient preparation, and software basics. The tube, detector, gantry mechanics, calibration, and electrical systems are for factory-trained technicians only.
| Symptom | Likely causes | What to try | When to call a technician |
|---|---|---|---|
| Double contours or blurred edges throughout | Patient movement during the scan | Improve stabilization; shorter scan protocol if available; coach the patient | If motion artifacts appear with well-stabilized phantoms |
| Bright streaks and dark bands near crowns, implants, or posts | Metal artifacts (beam hardening and scatter) | Use the software's metal artifact reduction if available; adjust FOV to exclude metal where possible | Not usually; it is a physics limitation |
| Rings or circular artifacts centered in the volume | Detector calibration issue or defective pixels | Run a phantom scan to confirm | Yes, for detector calibration |
| Region of interest cut off | FOV placement, positioning lights misread | Use a scout image; recenter | If lights and FOV do not match on a phantom |
| Very noisy images | Low-dose protocol used for a fine-detail question, large patient, wrong size setting | Select the protocol that fits the question and patient size | If standard protocols are noisy on a phantom |
| Reconstruction slow or failing | Workstation under spec, full disk, GPU driver | Free storage; restart; check the manufacturer's workstation specs | Call the dealer or IT if hardware is under spec |
| License or activation error | Expired license, hardware key missing, workstation change | Contact the manufacturer or dealer with the serial number | Dealer support |
| Rotation stops or unit shows a mechanical error | Collision sensor, patient contact, drive fault | Check for obstructions and patient contact; do not force the arm | Always if it recurs |
| Tube or generator error codes | Tube fault, overheating, electrical issue | Stop use; record the code | Always |
Safety and compliance
- FDA: dental CBCT is regulated under 21 CFR 892.1750 and the radiation performance standards in 21 CFR Part 1020, including the computed tomography section. The installer files a report of assembly.
- State radiation control program: registration, shielding plans, acceptance testing, QA programs, operator credentials, and inspection intervals vary by state and are often stricter for CBCT than for 2D units. Find your program through the CRCPD directory, and see our registration and inspection guide.
- Dental board: who may operate a CBCT is set by your state and may differ from who may take a pan.
- Infection control: disposable covers and disinfection of contact surfaces per the IFU and CDC guidance.
- Records and privacy: volumes are patient records. Retention, backup, and secure sharing with labs, surgical guide companies, and radiologists belong in your HIPAA program. See the compliance chapter.
General information only, not legal or regulatory advice. Confirm current requirements with your state radiation control program and dental board.
Buying new vs. used
With CBCT, the purchase price is often the smaller part of the installed cost. Software licensing, shielding, installation, calibration, testing, and the workstation can add a great deal, and license transfer rules differ by manufacturer. Our used CBCT buying guide covers these in detail, with a hypothetical installed-cost example.
CBCT practice-fit checklist
- FOV options match the procedures you will actually do, with a small FOV available for endo and single sites
- Voxel and dose protocols include high-resolution, standard, and low-dose or pediatric options
- Written software licensing terms for your office, including planning modules and extra viewing seats
- Interpretation plan decided: in-house reading, radiologist referral, or both
- State registration, shielding plan, and testing requirements confirmed for your room
- Room footprint, clearance, electrical, and network confirmed against the install guide
- Workstation meets current manufacturer specs, with a supported operating system
- QA phantom and positioning accessories included
- Service plan and parts availability confirmed for the model
- Referral volume and fee assumptions checked before committing
Red flags: a unit whose manufacturer will not license software to a new owner at a new address; no calibration history; a missing QA phantom; a workstation on an unsupported operating system; a unit deinstalled without transport locks; an FOV smaller than your planned procedures need.
Rough price ranges and lifespan
One national reseller lists new dental CBCT systems at roughly $60,000 to $120,000 and used or refurbished systems at roughly $20,000 to $60,000, as noted in our used CBCT guide. Treat those as rough market signals that vary by model, FOV, ceph, condition, region, and year. Mechanically, units can serve for a decade or more; the practical limits are tube and detector life and software support. See equipment lifespan by category and, for tax treatment, Section 179 for dental equipment (confirm with your CPA).
Brands and models you will see
Examples include Planmeca (ProMax 3D series and Viso), Carestream Dental (CS 8100 3D, CS 8200 3D, CS 9600), Dentsply Sirona (Orthophos 3D models such as the Orthophos SL), Vatech (PaX-i3D and Green series), and DEXIS (OP 3D models and the i-CAT line).
Related guides
Pair this guide with panoramic units for 2D imaging and intraoral scanners, since scans and volumes are merged for guided implant surgery. Printed surgical guides are covered in dental 3D printers. For buying, read buying a used CBCT and browse the marketplace.
Always follow the manufacturer's instructions for use (IFU) for your specific model. Repairs involving electrical, pressure vessel, radiation, or gas line work belong with a qualified technician. Infection control and radiation rules vary by state. Prices are rough ranges that vary by model, condition, region, and year. ChairsideSource is not affiliated with any manufacturer named here.