Most people have ridges on their tongues and it may simply be due to the way their teeth press into their tongues (you have probably notices this in the morning, because the mouth is inactive while you sleep). Another reason you might also see ridges if you have a fissured tongue which is a long crack down the middle of the tongue, and it's just something you’re born with.
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Looking Even though it sounds disgusting and scary, calm down. If you actually have this condition or someone you know has it, it isn’t dangerous because this alarming-looking condition is actually benign. It's sometimes associated with antibiotic use, a yeast infection, diabetes, cancer therapies, or poor oral hygiene. It happens when "the cells on your tongue grow faster than your body can shed them. But rest assured that this condition generally goes away on its own. Your doctor would explain to you that there is no actual hair on your tongue, it just looks like that.
This could signal of a chronic condition called oral lichen planus, which occurs when the immune system attacks cells in the mouth. Middle-aged women are most commonly affected. Usually, when the patient doesn’t feel any pain the doctor probably won't treat it, but would probably monitor your symptoms, because you might be at higher risk of developing oral cancer in those areas. In case of pain, the doctor subscribes drugs such as a corticosteroid, a retinoid, or an immunosuppressant.