CBCT in Paediatric Dentistry: When Is 3D Imaging Justified in Children?

CBCT paediatric dentistry is one of the most important topics in dental imaging today. Yet many referring clinicians remain uncertain about when cone beam CT is genuinely justified for younger patients. This guide covers the current evidence base. It also explains the UK regulatory framework and the practical steps every referring dentist should follow before requesting a paediatric CBCT scan.

Quick Answer: When Is CBCT Paediatric Dentistry Imaging Justified?

CBCT is justified in children when conventional 2D radiographs cannot answer the clinical question. In addition, the expected diagnostic benefit must outweigh the additional radiation exposure. The most common justified indications include localising impacted or ectopic teeth and assessing dental trauma. Evaluating supernumerary teeth and planning orthodontic or surgical interventions also qualify. Every referral must satisfy the IR(ME)R 2017 justification requirement. Furthermore, the field of view should always be kept as small as diagnostically appropriate.

Why CBCT Paediatric Dentistry Cases Require Extra Consideration

Children are not small adults when it comes to ionising radiation. Their tissues are more radiosensitive because cells actively divide during growth. According to research published in the European Archives of Paediatric Dentistry, a child under 10 carries approximately three times the relative radiation risk of an adult. In particular, the thyroid dose in a 10-year-old can be up to four times greater than in an adult.

However, these differences do not mean CBCT should be avoided in children. Instead, they mean that the decision to image must follow clear clinical justification. Appropriate dose reduction protocols must also be in place. For this reason, CBCT paediatric dentistry referrals demand a higher threshold of justification compared with adult imaging.

SEDENTEXCT and DIMITRA: The Guidance Framework for Paediatric CBCT

The SEDENTEXCT guidelines, published by the European Commission in 2012, provide the most widely referenced selection criteria for dental CBCT. Specifically, they identify several clinical categories where CBCT may be indicated in children. These include assessment of localised developing dentition and generalised developing dentition. Dental trauma evaluation, surgical assessment, and endodontic applications also feature.

However, SEDENTEXCT does not provide specific paediatric dose protocols. The DIMITRA project fills this gap. DIMITRA specifically recommends using small fields of view, typically 8 x 8 cm or smaller. This approach minimises radiation exposure while maintaining diagnostic image quality. Importantly, a smaller field of view reduces both the irradiated volume and the effective dose to the child.

Together, SEDENTEXCT and DIMITRA form the evidence base that supports justified CBCT use in paediatric patients. As a result, clinicians should reference both when documenting their clinical reasoning for a CBCT referral.

Clinical Indications for CBCT Paediatric Dentistry Referrals

Research across three UK paediatric dental departments found that the most common indication for CBCT in children was localisation of impacted teeth. This accounted for approximately 36% of all paediatric CBCT examinations. The remaining indications break down as follows.

Impacted and Ectopic Teeth

Palatally ectopic maxillary canines represent one of the most frequent reasons for requesting a paediatric CBCT. In particular, CBCT reveals the three-dimensional relationship between the ectopic canine and the roots of adjacent teeth. It also shows the labial or palatal bone plate position. This information directly influences treatment planning. Specifically, it determines whether surgical exposure, orthodontic traction, or extraction is appropriate. 3Beam’s guide to CBCT in orthodontics and impacted canines covers this clinical scenario in detail.

Supernumerary Teeth

Supernumerary teeth, especially mesiodens in the premaxilla, frequently present in children. Conventional periapical and OPG radiographs often cannot determine the precise buccopalatal position. Similarly, they may not show the proximity to developing permanent tooth germs. CBCT provides all of this information in a single scan. For more on this topic, see our article on CBCT for supernumerary teeth.

Dental Trauma

Following dental trauma in the mixed dentition stage, CBCT can detect horizontal root fractures. It also identifies lateral luxation injuries and alveolar bone fractures. Periapical radiographs may miss these findings entirely. A study in the European Archives of Paediatric Dentistry confirmed dental trauma was among the top three indications for CBCT in UK paediatric departments. Our separate guide covers CBCT for dental trauma and root fracture detection.

Orthodontic Assessment

Beyond impacted canines, orthodontists may request CBCT for skeletal assessment in growing patients. Airway analysis in suspected obstructive sleep apnoea is another common reason. Evaluation of condylar morphology also features. However, the SEDENTEXCT principle of net benefit still applies. If a lateral cephalogram or OPG provides sufficient information, then CBCT should not be requested as a routine orthodontic record.

Endodontic Applications

In the permanent dentition of adolescents, CBCT may help with complex endodontic problems. Examples include missed canals, internal resorption, or suspected vertical root fractures. These indications mirror adult endodontic CBCT use. However, clinicians should consider the patient’s age and cumulative radiation history.

Radiation Dose and Field of View Optimisation for Children

Understanding comparative radiation doses helps clinicians make informed referral decisions. A single OPG delivers an effective dose of approximately 7 microsieverts (μSv). By comparison, a small-field CBCT scan typically delivers 30 to 80 μSv. Meanwhile, a large-field CBCT can reach 150 to 400 μSv. These figures depend on the equipment and exposure parameters used.

Consequently, field of view selection is the single most important dose reduction strategy. A 5 x 5 cm field centred on a specific region delivers a fraction of a full maxillofacial CBCT dose. At 3Beam, our Morita Accuitomo and Veraview scanners offer a range of field sizes. Our radiologists work with the referrer to select the smallest field that answers the clinical question. For a detailed breakdown, refer to our guide on radiation dose in modern CBCT machines.

In addition, paediatric exposure settings should always be applied. These include reduced mA and kV parameters. Selecting a lower resolution mode is appropriate when ultra-high resolution is not clinically necessary. Correct patient positioning is also essential to avoid repeat scans.

IR(ME)R 2017 and the Referrer’s Responsibility

Under the Ionising Radiation (Medical Exposure) Regulations 2017, every CBCT referral in the UK must be individually justified. This applies to children as it does to adults. However, paediatric cases receive even greater scrutiny given the higher radiosensitivity of young patients.

The referrer has a legal duty to provide sufficient clinical information. The practitioner authorising the exposure uses this information to make a justification decision. In practice, this means the referral must clearly state the clinical question CBCT is expected to answer. It must also note what conventional imaging has already been obtained. Finally, it should explain why 2D imaging was insufficient.

For example, a well-justified paediatric CBCT referral might read: “13-year-old, palatally ectopic upper right canine confirmed on OPG and parallax. CBCT requested to determine buccopalatal position relative to lateral incisor root and plan surgical exposure.” For a fuller discussion, see our article on CBCT referral justification and IR(ME)R 2017.

How 3Beam Reports Support CBCT Paediatric Dentistry Cases

When a referring clinician sends a paediatric patient to 3Beam, the scan uses the smallest appropriate field of view. Paediatric exposure protocols are applied as standard. Where requested by the referrer, every CBCT includes a formal report from a UK Dental Radiologist. Dr Mandy Williams provides a structured clinical interpretation covering all relevant findings.

For paediatric cases specifically, the report addresses the clinical question posed by the referrer. It describes findings in relation to the developing dentition. It also flags any incidental findings that may require follow-up. This is particularly valuable in complex cases involving impacted teeth, trauma, or suspected pathology. The radiologist’s interpretation provides an additional layer of clinical assurance for the referring dentist and the patient’s family.

Same-day and next-day appointments are available at 3Beam’s 86 Harley Street imaging centre. The referring clinician receives the report and images electronically, typically within 24 hours.

Frequently Asked Questions

Q: At what age can a child have a CBCT scan?
A: There is no absolute minimum age for CBCT. The decision depends on clinical need, not age alone. If a conventional radiograph cannot answer the clinical question, the scan can be justified at any age. In practice, most paediatric CBCT scans are performed on children aged 7 to 16.

Q: Is CBCT safe for children?
A: CBCT is safe when clinically justified and performed with dose reduction protocols. Modern scanners deliver effective doses as low as 30 μSv for small-field scans. This is comparable to a few days of natural background radiation. The key is justification: the diagnostic benefit must outweigh the small additional radiation risk.

Q: Can a GDP refer a child for CBCT?
A: Yes. Any registered dental practitioner can refer a child for CBCT under IR(ME)R 2017. The referral must be clinically justified and include sufficient clinical information. Specialist status is not required. However, the referring dentist must demonstrate that 2D imaging alone is insufficient.

Q: What field of view should I request for a paediatric patient?
A: Always request the smallest field that answers the clinical question. For a single impacted tooth, a 5 x 5 cm or 4 x 4 cm field is typically sufficient. 3Beam’s imaging team selects the appropriate field size in consultation with the referrer before the scan.

Q: How does a paediatric CBCT dose compare with an OPG?
A: A standard OPG delivers approximately 7 μSv. A small-field CBCT delivers approximately 30 to 80 μSv. This is roughly 4 to 11 times the dose of an OPG. However, CBCT provides three-dimensional diagnostic information that an OPG cannot offer.

The Bottom Line on CBCT Paediatric Dentistry

CBCT paediatric dentistry is not about routine 3D imaging for every child. Instead, it centres on recognising the specific clinical scenarios where CBCT provides essential diagnostic information. Impacted teeth, dental trauma, supernumerary localisation, and complex orthodontic assessment represent the core justified indications. Every referral must satisfy IR(ME)R 2017 requirements. Dose optimisation through small field of view selection and paediatric exposure settings is non-negotiable.

For referring clinicians who need CBCT for a paediatric case, 3Beam offers specialist imaging with dose-optimised protocols and consultant radiologist reporting at 86 Harley Street.