Hello,

Thanks for writing in.

As per the reports produced, the black spot appeared may be due to any of the mentioned factors-
1. Niacin deficiency
2. Oral habits-tobacco/pan chewing
3. Traumatic injury
4. Congenital
5. Medications

I would suggest you to get the biopsy report of the lesion regarding final diagnosis and treatment plan. Direct clinical examination is mandatory to study the type of lesion and chance of being cancerous.
Meanwhile-
1.     Niacin-6 mg daily supplements can be administered
2.     Stop usage of tobacco/pan chewing if you practice any
3.     Consult your physician and replace the drugs if causing adverse effects as such, ie, black spot under tongue.
4.     Always brush your teeth carefully without causing trauma to the affected site.

Hope this helps.

Please feel free to ask further concerns.
I wish you good health.

Regards
Dr. Bindiya Bhaskar.

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