Exogenous pigmentation

1. Accidental:

• Foreign substance – Pencil graphite

2. Iatrogenic:

• Amalgam tattoo:
  • Condensation of mercury in abraded gingiva/breakage of filling
  • Histology: Dark granules along collagen bundle + multinucleated cells

• Chlorhexidine mouthwash:
  • Yellow brown on surface of oral tissues and surface of teeth (cervical + interproximal)

3. Drugs and heavy metals:

• Lead & bismuth – blue black deposits along gingival margin

4. Localized:

• Hairy tongue – green brown on dorsum, overgrowth of filiform papilla by chromogenic bacteria
• More under white lesions
• Click here for picture

5. Superficial staining of oral mucosa:

• Topical medications
• Smoking
• Tobacco
• Foods/drinks

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Endogenous pigmentation (melanotic lesions)

1. Developmental causes:

• Racial pigmentations
• Naevi/mole
• Peutz-Jeghers syndrome
• Polyostotic fibrous dysplasia
• Neurofibromatosis

2. Acquired causes:

• Systemic disease – Addison, HIV
• Smoking
• Hyperkeratosis and chronic inflammation/trauma
• Drugs (minocycline)
• Idiopathic oral melanotic macules
• Lentigo simplex

3. Malignant causes:

• Malignant melanoma
• Melanotic neuroectodermal tumor of infancy

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Other endogenous pigmentation

• Blood breakdown products and other disturbances of iron metabolism

1. Hemoglobin: Blue, red, purple

• Kaposi’s sarcoma
• Varix/hemangioma
• Hereditary hemorrhagic telangiectasia (HHT)

2.Hemosiderin/bilirubin: Brown

• Ecchymosis
• Petechia
• Hemochromatosis
• Varix/hemangioma

3. Melanin: Brown, black, grey

• Melanotic macule
• Basilar melanoma
• Naevus
• Melanoma