This retrospective observational study aimed to determine the prevalence and anatomical distribution of incidental findings (IF) and actionable findings (AF) identified on cone-beam computed tomography (CBCT) scans obtained for dental implant planning at an academic imaging centre. The study also examined associations between IF/AF and patient demographic and imaging variables, and characterized findings deemed actionable based on oral and maxillofacial radiologist (OMR) recommendations.
The study reviewed consecutive CBCT scans obtained for implant planning at the Advanced Imaging Centre, Mike Petryk School of Dentistry, University of Alberta, from July 2021 to July 2024. Institutional Research Ethics Board approval was obtained (Pro00120261). The investigation followed STROBE reporting guidelines. No additional imaging was obtained for research purposes; all records were fully anonymized and the requirement for informed consent was waived by the ethics board.
A structured, zone-based evaluation protocol was used to systematically assess four anatomical regions on each full-volume CBCT:
Findings unrelated to the implant planning site were classified as incidental findings (IF). Findings classified as actionable (AF) were those for which the OMR report recommended further evaluation, referral, or management. The AF classification was based on reporting recommendations rather than confirmed downstream clinical outcomes.
All adult patients (≥18 years) referred for CBCT imaging for dental implant planning during the study period were eligible. Scans were included if they had a complete radiology report interpreted by an OMR. Scans were excluded if the OMR report was missing, datasets/reports were incomplete, or a duplicate scan from the same patient was present during the study period. The final sample comprised 368 consecutive CBCT scans used for implant planning.
The investigators analyzed associations between IF, AF, CBCT field of view (FOV), age, and sex using univariate and multivariable methods. The study reported prevalence values and tested differences by demographic groups and imaging parameters. Where multivariable models were used, they examined whether age groups or sex predicted AF, noting overall model significance where relevant.
Incidental findings were reported in 257 of 368 scans (69.8%). Findings classified as actionable based on OMR recommendations were present in 199 patients (54.1%). These frequencies reflect report-based detection and recommended follow-up rather than confirmed clinical outcomes.
Findings were distributed across the four defined anatomical zones. The most prevalent specific findings across the cohort involved the maxillary sinus (35.1%), cervical spine (27.4%), tonsils (15.8%), TMJ (11.7%), and vasculature (8.4%). Zone-specific patterns included a higher frequency of Zone 2 abnormalities (zygomaticomaxillary/orbital/TMJ region) in certain subgroups, as detailed below.
Prevalence of IF increased with age: 50% in patients 40 years or younger versus 78.8% in patients older than 70 years. IF were more prevalent in males than in females (76.2% vs. 64.5%; p = 0.01).
In univariate analyses, AF were not significantly associated with sex (p = 0.97) or age (p = 0.25). Multivariable analysis identified higher odds of AF in patients older than 70 years, although the overall multivariable model was not statistically significant.
Zone 2 findings were more common in females than males (21.5% vs. 7.1%; p < 0.001). Regarding imaging extent, IF were most common in medium FOV scans (72.2%). AF frequency did not vary significantly by FOV (p = 0.94).
The study demonstrates a high prevalence of radiographic findings beyond the primary implant site on CBCT scans used for implant planning. Over two-thirds of scans had incidental findings and roughly half were classified as actionable by the reporting OMR. These results underscore the importance of comprehensive interpretation protocols and specialist reporting for CBCT studies in implant dentistry to ensure that extra-regional findings are recognized and appropriately managed.
The AF classification in this study is report-based (recommendations in OMR reports) and does not equate to confirmed clinical diagnoses or outcomes; this distinction was explicitly made by the authors. The single-centre academic setting may reflect local referral patterns, imaging protocols, and specialist reporting practices, which could limit generalizability. The dataset is not publicly available due to ethical and legal confidentiality restrictions, though qualified researchers may request access through the University of Alberta Research Ethics Office as described in the article.
IF and report-classified AF were highly prevalent on CBCT scans obtained for implant planning at this academic imaging centre: IF in 69.8% and AF in 54.1% of scans. Findings occurred across multiple anatomical zones and were associated with age and sex, while AF did not vary by FOV. The study supports systematic CBCT interpretation and specialist reporting in implant planning to identify clinically relevant extra-regional findings. Data underlying the study are restricted for confidentiality; access can be requested from the University of Alberta Research Ethics Office per the article's Data Availability Statement.