A systematic review on incidental findings in cone beam computed tomography (CBCT) scans

Cone beam CT's use (CBCT) in dentistry is increasing. Incidental findings (IFs: discoveries unrelated to the original purpose of the scan), are frequently found as a result of a large field of view. The aim of the systematic review is to analyze present literature on IFs using CBCT.

The authors searched online databases of studies and assessed the prevalence of IFs among patients undergoing head and neck CBCT scans. STROBE criteria was used to evaluate the quality of the studies.

The original search retrieved 509 abstracts of which only 10 articles met the inclusion criteria. The sample size varied between 90 and 1000 participants. The frequency of IFs of the selected articles were 24.6-94.3%. The most common non-threatening IFs were found in the airway, such as mucous retention cyst (55.1%) and sinusitis (41.7%). Other non-threatening IFs were soft tissue calcifications such as calcified stylohyloid ligament (26.7%), calcified pineal gland (19.2%), and tonsillolith (14.3%). Threatening IFs were rare findings (1.4%). Three articles reported incidental carotid artery calcifications with a prevalence of 5.7-11.6%. Pathological findings were not common between the articles, but still relevant (2.6%). The studies had a risk of bias varying from moderate to low.

There is a high frequency of IFs, yet not all of them require immediate medical attention. The low prevalence of threatening IFs emphasizes that CBCT should not be considered a substitution for conventional radiographs, but when used, the scans should be evaluated by a maxillofacial radiologist.