Definition: An abnormal curvature of a root or roots.
Location: Any tooth in the oral cavity.
Shape: Root tapering towards the apex with severe curvature.
Internal: Radiopaque, same radiopacity as tooth structure.
Number: May be single or multiple.
Tip: Facial or Lingual curvature of the roots may be difficult to detect on a 2D image such as a periapical. Sometimes, this will have a target or bulls-eye appearance, but not always.
(note the almost 90 degree curve of the lateral incisor)
(note the mandibular first molar roots)