Identification of specific panoramic high-risk signs in impacted third molar cases where cone beam computed tomography changes the treatment decision

Abstract Objectives The aim of this study was to investigate the treatment decisions of oral-maxillofacial surgeons in the management of impacted lower third molars (M3) according to panoramic radiography (PR) and cone beam computed tomography (CBCT) risk analysis. Methods Ten surgeons analyzed 40 deliberately selected M3 cases showing one or more panoramic high-risk signs: 1) darkening of the root, 2) interruption of the white line, 3) diversion of the inferior alveolar canal (IAC), 4) narrowing of the IAC, and 5) two or more signs occurring simultaneously (including darkening and/or interruption of the IAC). After evaluating the PR images, the observers analyzed the patients’ CBCT images. The treatment decision (extraction vs. coronectomy) and surgical technique (number of planned tooth sections) were recorded. Results Direct contact between the M3 and IAC, together with narrowing and/or fenestration of the IAC in the CBCT coronal slices, were observed most frequently when two or more panoramic signs were seen simultaneously in the PR images (odds ratio [OR]:7.2, p=0.021). CBCT findings led to a significant decrease in the number of coronectomy decisions (23 vs. 14.5%, p=0.002), which was most prominent in the groups showing panoramic signs of darkening (∼50%, p=0.007) and narrowing (∼66%, p=0.044). A significant number of extraction decisions were modified to coronectomy when two or more panoramic signs occurred together (OR: 7.9, p Conclusions The results showed that the surgeons’ confidence in treatment decision increased after CBCT imaging, resulting in lesser number of coronectomy decisions. CBCT information that changed a previous coronectomy decision to extraction was most frequently observed in cases presenting darkening and narrowing PR signs. The chance of changing an extraction decision to a coronectomy decision after evaluating the patient’s CBCT images was the highest when two or more PR signs were observed simultaneously.