Pathology · single question
A maxillary premolar tooth appears very dark on the buccal surface. What is the MOST likely cause?
Show answer and explanation
Correct answer: A. Amalgam tattoo
- A. Correct. A dark discoloration on the BUCCAL surface of a maxillary premolar — especially when it appears blue-gray, well-defined, and flat — is MOST likely an AMALGAM TATTOO. This occurs when amalgam particles from prior dental work (old restorations, extractions) are inadvertently incorporated into the adjacent mucosa, producing a blue-gray/black pigmentation.
- B. Incorrect. Melanotic lesions can occur but are less common on the buccal of a premolar; amalgam tattoo is the most likely explanation in this context.
- C. Incorrect. Vascular lesions (hemangiomas, purpura) blanch on diascopy — an amalgam tattoo does not blanch.
- D. Incorrect. A varix is a dilated vein, typically found on the ventral tongue or lower lip in older patients — not characteristically on the buccal of a premolar.