I've seen both your photos, I wish they were better focused though :-(
From what I can see, the white patches are quite harmless. At best they are simply excess keratin deposits. This occurs at places where the mucosa is tightly attached to the underlying bone, that is the gums and the palate.
It needs no intervention.
At best, this is a candidial infection
. I suggest you start swishing with a mouthwash like Listerine. That should have an effect is reducing the white patches within a weeks time.
If they are painting, get a local anesthetic gel from the pharmacy and apply it to the sore areas.
This is nothing dangerous and does not need a biopsy.
Hope this answers your question. Feel free to contact me again for more information.
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