due to repeated biting of cheek thickening of mucosa occurs which generally is not a thing to worry. Start betadine
gargles and try not to bite again on that part. Ask ur dentist
to examine if there is a need for a tooth extraction or some sharp tooth cusp has to be smoothened... itching can be there cos of lodgement of microrganisms so maintain oral hygiene
. U can also start warm saline gargles 3-4 times a day..