Hi! If this is NOT near the lower back molars, I would begin warm salt water rinses 3-4 times a day. If the sore is at this location, it could be a parotid gland issue. Let's try the salt water first and then take it from there. You may have bit your cheek and the soreness takes 5-7 days to heal. If the salt water does not stop this in 2 days, you should see your dentist to make sure this is not a stone or a blocked duct. If you have any other questions, please ask. I will help you all that I can.
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