Black hairy tongue is a temporary, harmless oral condition that gives the tongue a dark, fury appearance. It is mainly caused by bacteria or fungi in the mouth, which makes the tongue black and hairy.
Symptoms: Due to growth of fungi it causes burning sensation called glossopyrosis. Some even feel tickling on the roof, nausea, metallic taste and even bad breath.
Treatment: Maintenance of proper oral hygiene by brushing twice a day.
The no. of people who are suffering has been increasing.