Definition: A developmental indentation of the mandible, often caused by a finger-like projection of salivary gland tissue.
Radiographic Features:
- Location:
- Submandibular gland type: Posterior mandible, inferior to inferior alveolar nerve canal
- Sublingual gland type: Anterior mandible
- Edge: Well-defined, corticated
- Shape: Round to ovoid
- Internal structure: Radiolucent, unilocular
- Other: None specific
- Number: Typically single, rarely multiple
Key points:
- Also known as static bone cavity or lingual mandibular depression
- Not a true cyst (lacks epithelial lining)
- Usually asymptomatic and discovered incidentally
- More common in males and older adults
Clinical significance:
- No treatment required; benign condition
- Important to differentiate from other radiolucent lesions of the mandible
- May be mistaken for cystic or neoplastic lesions
- Periodic follow-up recommended to confirm stability
Note: Additional imaging modalities (e.g., CT, MRI) may be useful to confirm the diagnosis by demonstrating continuity with salivary gland tissue. Biopsy is generally unnecessary unless atypical features are present.