Hello,
Burning sensation as well as
metallic taste in mouth may be due to impacted wisdom teeth which is inflamed.
I would advice you to visit a
dentist and get the wisdom teeth extracted or saved.
Decayed teeth if present,has to be extracted or restored.
Use warm saline rinse to gargle.
Rinse your mouth after every meals.
Use desensitizing toothpaste and soft bristled toothbrush to clean your teeth.
Maintain
oral hygiene well.
Hope this helps.