A global overview of the use of cone beam computed tomography in dentistry: a bibliometric review focusing on paediatric patients

Citation analysis and radiation safety protocols

The most cited article, published in 2015, is a systematic review that aimed to analyse dose measurement and estimate the effective dose for performing CBCT with dental applications.²¹ The study reported that the effective dose for CBCT in children ranges from 13 to 769 μSv for large or medium fields of view and 7 to 521 μSv for small FOVs. The high number of citations reflects the importance of understanding CBCT radiation exposure in paediatric patients.

Other highly cited studies also focus on the risks associated with radiation exposure in children. A UK cohort study involving approximately 175,000 individuals exposed to head CT scans during childhood reported that cumulative doses of 50 mGy nearly tripled the risk of leukaemia, while 60 mGy nearly tripled the risk of brain cancer.²⁵ Similar results were observed in an Australian cohort of 10.9 million people aged between 0 and 19, showing a 24% increase in the incidence of cancers, including brain cancers and leukaemia, after exposure to CT scans. This incidence was correlated with increased dose and young age at the time of exposure.²⁶ Although the risk of dentomaxillofacial imaging using CBCT is small for an individual, when multiplied by the large population of patients exposed to diagnostic imaging, the risk of radiation becomes a significant public health problem, especially in children and adolescents.²¹

When comparing this study with other bibliometric studies,^17,18,27 a significant number of self-citations can be observed. Although this practice is not widely accepted in the scientific community, it can be considered a natural consequence. Research groups specialising in CBCT and radiation safety may frequently reference their previous studies as part of an ongoing effort to refine and improve imaging protocols.²⁸ In this context, the most cited studies tend to focus on radiation dose assessment, risk evaluation, and strategies for dose optimisation, reflecting the broader concern with radiation safety in paediatric imaging.

The use of CBCT in paediatric dentistry requires adherence to well-defined radiation protection protocols to balance diagnostic benefits and exposure risks. The ALARA (As Low As Reasonably Achievable) principle has been widely established as the foundation of radiation safety, advocating for exposure minimisation while maintaining adequate image quality.²⁹ However, recent studies have expanded this approach, introducing the ALADA (As Low As Diagnostically Acceptable) principle, which considers that dose reduction should not compromise diagnostic utility, and the ALADAIP (As Low As Diagnostically Acceptable for an Individual Patient) principle, which emphasises patient-specific optimisation strategies.³⁰ The DIMITRA Project⁴ aligns with these concepts by advocating for stricter justification criteria and individualised imaging protocols, ensuring that CBCT is only performed when conventional imaging is insufficient. Similarly, ICRP Publication 154 (2023)³¹ reinforces the need for patient-specific exposure adjustments, recommending collimation, reduced exposure parameters, and careful selection of the field of view (FOV).

Despite these structured guidelines, variations in clinical implementation remain a challenge. While some guidelines prioritise stricter justification to prevent unnecessary exposure, others emphasise standardised optimisation strategies. The integration of ALARA, ALADA, and ALADAIP suggests a shift towards a more patient-centred approach, balancing radiation protection with diagnostic accuracy. However, differences in the interpretation and application of these protocols may lead to inconsistencies in radiation dose management.

Year of Publication

The oldest article, published in 2008, proposes the use of reference points for cephalometric analysis using three-dimensional (3D) CBCT reconstruction with orthodontic indications.³² In this study, CBCT scans of 10 adolescents were used, and the authors indicated that the reference point with the highest intra-reliability was located between the two spinous foramina. With the indication of this cephalometric point, the authors proposed a tool that could be used as a reference for orthodontists when analysing 3D images since the use of this type of image, as it is an anatomically true representation (1:1 size), from which the sections can be displayed from any angle in any part of the skull and provided digitally on paper or film, can provide useful information for identifying teeth and other structures for diagnostic and descriptive purposes.

Since 2005, studies investigating or using CBCT in children and adolescents have gradually increased. A higher number of publications was observed in 2021, 2022, and 2023, reflecting continued interest in its applications and safety in paediatric dentistry. In 2023, the International Commission on Radiological Protection (ICRP) published the ICRP Publication 154, reinforcing the importance of optimising radiation doses in medical imaging, particularly for paediatric patients.³¹ The timing of this update and the increase in publications suggests that recent discussions on radiation protection may have contributed to a greater focus on CBCT protocols and dose optimisation for this population.

Publishing Journals

The American Journal of Orthodontics and Dentofacial Orthopedics was the journal with the highest number of published articles and, therefore, the highest number of citations. However, it was well below the JIF, occupying only seventh position. The JIF is the annual average of citations of the articles published by the journal over the last two years.³³ Although impact factors are widely used to assess journal influence, they do not necessarily reflect the quality or relevance of individual articles. Citation distribution within journals is not uniform, meaning that a high-impact factor does not indicate that all published studies receive the same level of recognition.³⁴ This may explain why researchers prioritise journals that align more closely with their specific field, such as paediatric dentistry and orthodontics, rather than selecting journals solely based on their impact factor ranking.

Study design and themes

The choice of study design plays an important role in the quality and reliability of research findings. In paediatric dentistry, the use of CBCT has been investigated using a variety of study designs, including observational studies, clinical trials, case reports and systematic reviews. Selecting the appropriate study design helps to address specific research questions, such as the applicability of CBCT from clinical diagnosis and treatment planning to the assessment of long-term outcomes.

The predominance of observational studies in this review aligns with previous bibliometric analyses in dental research, where observational designs are often favoured for their ability to collect data in real-world settings.^12,13 While observational studies provide valuable information on trends and associations in clinical practice, their limitations, such as the inability to establish causal relationships and control for confounding variables, should be acknowledged.¹⁹ Previous studies, including those on CBCT applications in orthodontics and endodontics, have also highlighted the usefulness of such designs in documenting treatment outcomes and identifying practical applications.^3,11

However, the low proportion of randomised controlled trials (less than 1%, with only five studies) identified in this global review may be attributed to the ethical and practical challenges of conducting trials involving ionising radiation in paediatric populations. Given the risks associated with radiation exposure, particularly the long-term risks of cancer, RCTs in this area are difficult to justify.²⁵ In contrast, controlled studies would offer a more rigorous assessment of outcomes and potential risks, particularly regarding radiation exposure in children.⁷ Instead, observational studies are more commonly employed, as they allow for the exploration of CBCT’s evolving role in treatments without the need for unnecessary radiation exposure.^17,34

Most of the studies included in this analysis used CBCT to plan and assess maxillary expansion, highlighting the importance of this technology in complex orthodontic diagnoses. CBCT is widely used to evaluate bone morphology and tissue response to rapid maxillary expansion (RME), particularly in children with maxillary atresia. Studies such as Fastuca et al. (2015)³⁴ demonstrate that CBCT provides detailed insight into airway changes following RME, allowing for accurate evaluation of skeletal and dentoalveolar modifications. Additionally, CBCT has proven essential for three-dimensional documentation of bone and dental movement, offering precision in post-treatment follow-up, which facilitates planning for additional interventions. However, the potential for CBCT to reduce radiation exposure in paediatric patients requires further exploration, particularly in optimising image acquisition protocols.

Another significant use of CBCT was in aiding endodontic diagnosis and treatment, with an increasing emphasis on its use to assess root canal volume and untouched areas after instrumentation, as discussed by Gogos et al. (2020).¹² CBCT offers high-resolution images, enabling precise three-dimensional visualisation of anatomical structures such as roots and canals, which are often challenging to assess in conventional two-dimensional radiographs. This accuracy facilitates the diagnosis of hidden pathologies and improves the success of endodontic treatments. However, there is an opportunity to expand research on the long-term impact of CBCT on clinical success in endodontic treatments, as well as its application in guided endodontic techniques.

CBCT was also widely used in the diagnosis and treatment of cleft lip and/or palate, where its ability to generate detailed three-dimensional images is indispensable for surgical planning. The clear visualisation of the palate and surrounding areas allows for accurate assessment of the cleft and associated bone structure. The CBCT has been widely used in preoperative planning and postoperative follow-up of these corrections, especially in paediatric patients. However, despite its widespread use, the challenge of minimising radiation exposure in children remains a priority, necessitating further studies focused on developing low-dose imaging protocols.¹⁷

Institutions and Authors

Different institutions carried out most of the studies. The University of Alberta in Canada emerged as the most important institution with the highest number of publications. This prominence can be attributed to the university’s robust research programmes in paediatric dental patients and its significant investment in imaging technologies. Ranked in the top 100 in the world and fourth in Canada,³⁵ the University of Alberta has extensive resources and expertise that are likely to contribute to its high output in this area. In addition, the presence of specialised research centres and strong collaborative networks with other leading institutions may enhance its ability to produce influential research in CBCT and paediatric dental patients, which may explain the significant number of articles in this bibliometric analysis.

Jacobs R was the most prominent author, focusing his articles mainly on observational and laboratory studies. His focus is on the assessment of radiation dose during cone beam computed tomography (CBCT) scans. On the other hand, the second most prominent author is Lagravere MO, whose production covers observational and interventional studies, with a particular emphasis on maxillary expansion. These authors, although clustered in 2018, belong to different research groups without any collaboration. These two authors stand out as significant contributors to the field, each bringing valuable perspectives and knowledge to research related to CBCT and paediatric dental patients.

Strengths and limitations

The findings of this bibliometric review have important clinical implications for professionals in the field of paediatric dental patients. The principal application of CBCT in maxillary expansion, as evidenced in this review, highlights its efficacy in the differential diagnosis and treatment planning of patients with complex maxillofacial conditions. For clinicians, an awareness of these trends can facilitate the identification of cases in which CBCT should be used to optimise patient outcomes. This encompasses cases that demand precise imaging for orthodontic assessments, surgical planning, or the evaluation of cleft lip and palate. Furthermore, the data suggests an increasing focus on reducing radiation exposure, which is vital for establishing safe practice protocols. Consequently, this review offers clinicians a detailed account of contemporary research trends, thereby facilitating the formulation of optimal practices and providing a foundation for evidence-based clinical decision-making.

Furthermore, this study did not impose any restrictions regarding publication year, citations, or language, thereby enabling a comprehensive and inclusive analysis of all documents pertaining to CBCT in paediatric dental patients up to the date of the research. This appears to be the inaugural bibliometric review to address this topic in such a comprehensive manner.

While this review offers a thorough examination of the use of CBCT in paediatric dental patients based on data from the Web of Science database, it is crucial to recognize certain limitations inherent in this approach. The decision to focus on a single database, excluding others such as Scopus or PubMed, might have restricted the breadth of the analysis. Consequently, some relevant studies published in other databases may not have been considered. This choice aligns with the methodology used in previous bibliometric reviews,^16,18 and was made to maintain consistency with established research practices. Nonetheless, to achieve a more exhaustive understanding of the available literature and reduce the risk of overlooking significant findings, future research would benefit from adopting a more inclusive search strategy that encompasses multiple databases. This approach could help mitigate the potential for biases associated with the selection of a single data source.