A Case Report of Black Hairy Tongue (Melanotrichia Linguae or Lingua Pilosa Nigra) Cureus Black hairy tongue syndrome Brown lesion on the tongue of a child Ohta 2024 Oral Diseases Wiley Online Library Successful treatment of melanotic hyperpigmentation of the tongue with a Qswitched Alexander laser: A case report Sun 2023 Photodermatology, Photoimmunology & Photomedicine Wiley Online Library Olanzapine Induced Black Hairy Tongue During Treatment of Hebephrenic Schizophrenia Decompensation: A Rare Case Report and Brief Review of the Literature Cureus