Although the cause of black hairy tongue is unknown, it has been suggested that some of the causes may be due to poor oral hygiene, antibiotic use, smoking, breathing through the mouth or not enough saliva is produced. It is a painless condition that occurs when the little bumps on your tongue grow long and they trap the bacteria that live in your mouth. It makes your tongue look black and hairy.
Brushing your tongue with a soft bristle toothbrush or using a tongue scraper will help, however for proper diagnosis of your individual case be sure to see your dentist as soon as possible.
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