Hello i have a medium size lump, in my mouth, under my lower back teeth, i have not had any pain, but i was wondering if it was ok for me to fly?

Well,...: A lump in your mouth usually would not preclude you from flying, but he lump needs to be assessed and evaluated by a health care provider. An ENT Dr. would be the best, if not an oral surgeon, etc.

No way 2 know unless: There is no way to know unless the nature of the lump is determined by a dentist. Better to have it treated or at least looked at by dentist first.

No problems : flying. Air travel can cause or worsen certain medical problems, but in your case is highly unlikely. If this lump does not go away or improve in another 7 to 10 days, you should see your dentist just to be sure. Take care.