A new systematic review in Clinical Oral Investigations pooled 19 studies and estimated that 36.7% of dental patients have at least one incidental finding on a panoramic radiograph. The figure is uncertain, with a 95% confidence interval of 22.9% to 53.1%, and the authors conclude that a justified image should be assessed for incidental findings by a specialist oral and maxillofacial radiologist or a suitably trained dentist.
Incidental findings are a routine part of panoramic imaging, according to a review published online on September 24, 2026. As of November 2026, it is a fresh look at how often they appear: the review pooled 25 studies, with 19 contributing to the headline figure. For dentists in Toronto and across Ontario, the practical question is less about the headline percentage and more about what happens after the image is taken: who reads all of it, how the reading is recorded, and where a finding goes next.
What did the panoramic radiograph review study?
The paper, "Incidental findings from panoramic radiographs: A systematic review with meta-analysis," appears in Clinical Oral Investigations (volume 30, issue 10). Its authors are Imboden-Ilia, Awaad, Inglezos, Eliades and Papageorgiou. The author affiliations include the Clinic of Orthodontics and Pediatric Dentistry at the University of Zurich.
The team searched eight databases from inception up to January 2026. They included 25 cross-sectional studies covering 66,882 patients from 15 countries, Canada among them. Most of the work came from university clinics (22 of 25 studies), and the largest group of studies (11 of 25) looked at patients seeking orthodontic treatment. The review describes incidental findings, as commonly defined, as unexpected radiographic observations unrelated to the primary purpose of the image that may still carry diagnostic or therapeutic relevance.
How common were incidental findings?
Individual studies reported a prevalence anywhere from 5.2% to 88.1%. The main meta-analysis, which covered 19 studies and 61,627 patients, produced a pooled estimate of 36.7%. Patients referred for temporomandibular joint disorders were left out of that analysis because the authors did not consider them representative of the average patient.
The spread matters as much as the average. The authors reported relative heterogeneity (I²) of 100% and a 95% prediction range of 2.88% to 91.88%, and they wrote that the confidence interval is more informative than the point estimate. Read the 36.7% as a sign that these findings are common, not as a number to expect in your own patient base.
Which findings appeared most often?
Across the 61 separate findings the review catalogued, several stand out for general practice. Most of these estimates come from a small number of studies and carry wide confidence intervals, so read them as rough signals:
- Tooth position and number: tooth impaction (10.5%) and hypodontia (4.5%).
- Odontogenic and periapical pathology: periapical lesions or rarefying osteitis (5.3%) and retained roots (5.3%). The authors note that retained roots and periapical radiolucencies may represent asymptomatic, previously undiagnosed endodontic disease.
- Soft-tissue calcifications: calcification or elongation of the styloid ligament (7.1%), vascular plaques (3.7%) and calcifications of the carotid artery (1.0%).
- Sinus and nasal findings: sinus pneumatization (50.6%), turbinate hypertrophy (7.0%) and mucosal thickening of the sinus (2.5%). The authors suggest the very high pneumatization figure likely reflects differences in how studies classified anatomical variation versus pathology.
- Other findings: vertebral anomalies (7.4%) and marginal bone loss (6.1%).
Many of these findings are clinically insignificant, the authors write, but some may have important implications for treatment planning or wider patient management.
What does the review say about carotid calcifications?
This is the finding most likely to prompt a difficult chairside conversation, so the wording counts. The authors state that carotid artery calcifications have been associated with atherosclerotic disease and an increased risk of future cardiovascular and cerebrovascular events. They also state that panoramic radiography cannot determine the presence or severity of carotid stenosis and should not be considered a diagnostic tool for vascular disease. Such findings, they write, may justify further medical assessment in selected patients.
The same caution applies to the sinuses. The authors point to the limits of panoramic imaging, including distortion, superimposition and its two-dimensional nature, and note that suspicious findings often require three-dimensional imaging or specialist evaluation.
Did prevalence differ by patient group?
Yes, and the differences between sample types were statistically significant. Note that the pediatric and third molar figures each rest on a single study.
Adults showed a higher prevalence than children (83.1% versus 52.7%, from 2 and 4 studies respectively), but that gap did not reach the review's 10% threshold for significance between subgroups (P = 0.13), and meta-regression found no significant effect of mean age. The authors separately reported 88.3% among patients referred for temporomandibular joint disorders, a group excluded from the main analysis.
How strong is the evidence?
The authors are direct about its weaknesses, and those limits should shape how you read every percentage above:
- All 25 included studies were cross-sectional.
- Only 7 of the 25 studies (28%) reported that the assessor was trained or calibrated beforehand, and the authors report that fewer than half employed certified oral and maxillofacial radiologists.
- Only 3 studies (12%) had assessors unaware of the reason the radiograph was taken.
- Only 7 studies (28%) had eligibility criteria that made their patients representative of the general healthy population.
- Studies with larger samples tended to show lower rates than studies with smaller samples.
- Certainty of evidence was not formally rated, because the authors say no guidance exists for systematic reviews of prevalence studies.
The review also cannot tell you what happens to patients afterward. The authors call for longitudinal studies on clinical significance, referral outcomes and the cost-effectiveness of managing these findings.
What should Ontario practices take from this?
The authors conclude that a justified panoramic image "should be adequately assessed for incidental findings by either a specialist oral and maxillofacial radiologist or a dentist with appropriate training and experience." That sentence pairs with the Ontario starting point. According to the Royal College of Dental Surgeons of Ontario (RCDSO), the Healing Arts Radiation Protection (HARP) Act requires that dental x-rays be prescribed by a dentist before they can be taken, and it precludes a set number of exposures or time-sequence radiographs without an individualized prescription based on a clinical examination. RCDSO's article, last updated in June 2024, says the daily photographic quality control requirements for digital radiography also apply to panoramic x-ray machines.
In other words, this review is not an argument for taking more panoramic images. It speaks to what you do with an image you have already justified. The suggestions below are EBIKO Dental's own editorial points for your team to consider, not findings from the paper or RCDSO requirements:
- Read the whole image every time. A consistent order of review (dentition, jaws, sinuses, temporomandibular joints, soft-tissue regions, spine) makes it harder to stop at the area of interest.
- Know your own limits. Agree in advance which appearances your dentists will manage and which go to an oral and maxillofacial radiologist or another specialist.
- Close the loop. A finding that needs follow-up helps nobody if it stays in the chart. Decide who tells the patient, who sends the referral or physician letter, and who confirms it was received.
Pro Tip: Pull 10 recent panoramic images and check whether each chart records a review of the full image and any follow-up. The gaps will show you where your process depends on memory.
Questions about Ontario-specific expectations are best directed to the RCDSO. For more practical reading for Canadian dental teams, visit EBIKO Dental.
EBIKO Dental will continue monitoring research on dental imaging and its implications for Canadian practices.
Sources
- Imboden-Ilia A, Awaad H, Inglezos E, Eliades T, Papageorgiou SN. Incidental findings from panoramic radiographs: A systematic review with meta-analysis. Clinical Oral Investigations, 2026;30(10).
- Open-access full text on Europe PMC (PMC13612610)
- RCDSO: X-ray safety requirements for all Ontario dentists
Frequently Asked Questions
Q: How common are incidental findings on dental panoramic radiographs?
A 2026 meta-analysis in Clinical Oral Investigations estimated that 36.7% of patients have at least one, with a 95% confidence interval of 22.9% to 53.1%. Individual studies ranged from 5.2% to 88.1%, so the authors caution that the pooled figure may be imprecise.
Q: Can a panoramic radiograph diagnose carotid stenosis?
No. The review's authors state that panoramic radiography cannot determine the presence or severity of carotid stenosis and should not be considered a diagnostic tool for vascular disease. They write that a calcification may justify further medical assessment in selected patients.
Q: Does this review mean Ontario dentists should take more panoramic images?
No. The review addresses images that are already justified. According to the RCDSO, Ontario's HARP Act requires a dentist's prescription before a dental x-ray is taken and precludes a set number of exposures or time-sequence radiographs without an individualized prescription based on a clinical examination.