It is difficult to give a rational opinion without a proper clinical examination or at least a look at the clinical picture of the affected area.
A detailed history regarding any episode of trauma or oral habits like tobacco usage also needs to be evaluated. There can be multiple reasons for the darkening and the burning sensation, which can range from fungal infection to conditions like lichen planus, but please understand that these are tentative suggestions based only on the description that you have mentioned.
Please visit an oral pathologist in your vicinity as soon as possible for a proper case evaluation so that the right treatment can be instituted after establishing the right diagnosis.
Regards.
Answered2017-09-22 12:54:35
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