Cross-sectional CBCT image of mandibular first premolar with a clearly distinguished C-shaped configuration. Image A illustrates canal shape from the coronal aspect. White arrow denotes root canal in the sagittal plane (B), and the orange arrow denotes the cross-sectional image (C).
Yu et al. BMC Medical Imaging 2012 12:18 doi:10.1186/1471-2342-12-18