Stafne defect

Dental panoramic radiograph showing Stafne defect in the right mandible, below the inferior alveolar nerve canal (arrowed, appears on lower left of image). This x-ray was taken for an unrelated assessment of wisdom teeth, and the Stafne defect was a chance finding.
Axial computed tomograph of the same person. The Stafne defect appears as a well corticated 1 cm round defect in the medial cortex of the mandible in the right angle of the jaw (arrowed).
Coronal computed tomograph of the same person (Stafne defect arrowed).

The Stafne defect (also termed Stafne's idiopathic bone cavity, Stafne bone cavity, Stafne bone cyst (misnomer), lingual mandibular salivary gland depression, lingual mandibular cortical defect, latent bone cyst, or static bone cyst) is a depression of the mandible, most commonly located on the lingual surface (the side nearest the tongue). The Stafne defect is thought to be a normal anatomical variant, as the depression is created by ectopic salivary gland tissue associated with the submandibular gland and does not represent a pathologic lesion as such. This cavity is commonly observed on panoramic radiograph.