sequestrae...i ahve been researching this since i think this is what i have im my gum, the dentist told me at first that it was a ulcer now i can see a piece f bony object protruding thruthe gum. and i hope it is out soon.....
it could also be an absess, or perhaps a fragment of the wisdom tooth was left behind. have it x-rayed and checked out.
It might be that you are traumatizing the tissue while eating. i would have it looked at by your dentist.