Thanks for writing to us.
Do you have the habit of tobacco or pan or betel nut chewing?
The above mentioned habits can predispose to black spots inside mouth.Vitamin deficiency
also can cause such lesions.
as well as clinical examination of the lesion will help to rule out the cause of lesion.
Meanwhile,gargle frequently with warm saline.
Maintain oral hygiene
Vitamin b-complex as well as iron supplements
has to be administered.
Hope this helps.