Introduction: The accessory foramina could not be identified on some imaging modalities such as surface-rendered images. The purpose of this study was to investigate the ability of surface-rendered images in detecting these foramina.
Materials and methods: We analyzed 20 accessory mental foramina (AMF) in nine mandibles removed from cadavers with cone-beam computed tomography (CBCT) and assessed in surface-rendered images. All AMF were divided into three groups depending on their visibility.
Results: Group 1 included AMF that were clearly visible as foramina, Group 2 were not clearly visible but could be recognized with concave parts, and Group 3 were not visible and the smooth surface of the bone was observed. Group 1 ranged from 1.3 to 5.1 mm2, Group 2 from 0.3 to 3.8 mm2, and Group 3 from 0.2 to 1.1 mm2. A statistically significant difference in the mean size between Groups 1 and 3 was observed. Even if the AMF are smaller (e.g., 1 mm in diameter), they should still be avoided to prevent injury.
Conclusions: The clinician should be aware that smaller foramina might not be detected on these images.
Keywords: anatomic variation; anatomy; cone-beam computed tomography; mandible; oral surgical procedures; three-dimensional.