Radicular cyst

This diagnosis code represents a true cyst of odontogenic origin that develops from epithelial remnants within the periodontal ligament, typically as a sequela of pulpal necrosis and inflammation. It is usually associated with the apex of a non-vital tooth and contains fluid.

Assign this code when documentation specifies a radicular cyst, periapical cyst, or apical periodontal cyst. This diagnosis is commonly made following radiographic imaging (e.g., periapical radiographs, CBCT) showing a well-defined radiolucency at the apex of a tooth with a history of pulpal pathology.

• Differentiate from other odontogenic cysts; specifically, do not confuse with lateral periodontal cysts.
• Ensure documentation clearly states "radicular cyst" or a synonym to support code assignment.
• Consider sequencing with codes for the underlying dental condition (e.g., pulpal necrosis) if still present and being treated.