Table 1.

Causes of intraoral pigmentation.

Endogenous	Exogenous
Hereditary or congenital	Medicationand toxicity related
Physiologic pigmentation (skin type 5-6)	Antimicrobial agents
Peutz-Jeghers syndrome	Antiarrhytchmic agents
Laugier-Hunziker syndrome	Oral contraceptives
	Cytostatics
Systemic or infectious	Smokers melanosis
Addison's disease
Petechiae, varices, or thrombus	Traumatic
	Haematoma
Neoplastic or melanin   related	Postinflammatory pigmentation
Naevi	Oral melanoacanthosis
Pigmented maculae
Mucosal melanoma	Other exogenous pigmentations
Kaposi's sarcoma	Amalgam tattoos
Haemangioma	Accidental graphite tattoos
	Tribal tattoos