Why are some people’s gum differently coloured?

Gums can range in hue from red to pink in appearance. Some people have brownish or darker gums as a result of their natural melanin pigment, while others may have black gums from birth due to other factors such as medications taken by their pregnant mother.
If your red or pink gums have lately turned black, it could indicate an underlying health problem.
Gums can turn black for a variety of reasons, including:
Poor oral hygiene, such as not brushing or flossing your teeth on a daily basis, can lead to plaque and tartar accumulation near the gums, resulting in gum discoloration and gum disease.
Excess plaque or tartar may necessitate a comprehensive dental cleaning.
Tobacco smoking produces patches of brown to blackish discolouration in your mouth, including your gums, lower lip, and cheeks.
Nicotine stimulates the melanin-producing cells known as melanocytes to create more melatonin, resulting in the effect.
These are types of drug that causes black gums.
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Amalgam tattoos are black, blue, or grey patches that form on the inside of your mouth, including the gums.
The deposition of amalgam (a combination used for fillings in crowns) in your gums causes them.
Pregnancy increases your susceptibility to develop plaque in your teeth and may even cause gum inflammation, resulting to dark gums, if you don’t practise basic oral hygiene.
Acute necrotizing ulcerative gingivitis, often known as trench mouth, is a gum infection that produces fever, painful gums, bleeding gums, excessive salivation, and poor breath. Gum disease can develop grey or black gums.
What is the treatment for black gums?
When the cause of black gums is removed, they frequently disappear. Quitting smoking, for example, can improve dental health and gum colour. Other preventive factors include following a dentist’s dental hygiene recommendations.
If your black gums are caused by a condition like Addison’s disease, your doctor will treat the underlying illness to slow down the growth of the disease.
Your dentist may suggest the following options if you wish to get rid of black patches on your gums for cosmetic reasons:
Using a scalpel to remove the black or discoloured gum tissue
Cryosurgery is a type of cryosurgery (freezing the affected gum tissue)
Gingival grafting for free (removing a piece of normal-colored tissue from the roof of the mouth and stitching it to the black gums)
Hope it helps!