The cause of black gums can be influenced by genetic factors. Where pigmentation of body parts, including gums, is darker than others. This is normal as a person's skin can be darker than others naturally. The cause of other black gums is due to the high levels of melanin or dark pigments in a person's body that causes the skin color, even the gums, to be darker than others.
Smoking habits and consumption of certain types of drugs can cause black gums. Changes in the color of the gums become darker in smokers is called smoker's melanosis. Smoker's melanosis results from an increase in the amount of melanin in a smoker's body. However, smoker's melanosis can disappear within 3 years from the time someone stops being a smoker.
Some drugs such as minocycline and tricyclic anti-depressant can also cause the gums to turn black. Even some types of restorations or dental fillings such as metal crowns can cause black gums. If you find your gums are black after taking the drugs above, immediately contact Nathan Guilford DDS for a further consultation.