Hi.This seems to be a case of Black hairy tongue and the causes include build up of bacteria or yeast in the oral cavity,repeated use of lozenges/mouthwashes, poor oral hygeine or repeated intake of tea/coffee etc.Consult your dentist to help you out with this.
Regards,
Dr.Sanchit Talwar,
MD (Skin & VD),
Consultant Dermatologist,
Dr Talwar's, Skin, Laser and Cosmetic Clinic
CHANDIGARH.
Answered2016-03-06 13:54:23
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