Oral pigmentation is a relatively common condition that may involve any portion of the oral cavity. Multiple causes are known, and they may range from simple iatrogenic mechanisms, such as implantation of dental amalgam, to complex medical disorders, such as Peutz-Jeghers syndrome. Local irritants, such as smoking, may also result in melanosis of varying degrees.  Oral pigmented lesions result from cellular hyperplasia that can range from benign nevi to fatal oral melanoma. Pigmented entities may arise from intrinsic and extrinsic sources. The color may range from light brown to blue-black. The color depends on the source of the pigment and the depth of the pigment from which the color is derived. Melanin is brown, yet it imparts a blue, green, or brown color to the eye. This effect is due to the physical properties of light absorption and reflection described by the Tyndall light phenomenon or effect. Oral conditions associated with increased melanin are common; however, those due to melanocytic hyperplasias are rare.