Recently, I had a clot in my mouth when I bit down on a breakfast bar and hit the upper front tooth with one of my lower teeth. The impact of the hit was severe and felt numb at first. The following day the pain started and swelling soon followed. I had to go to the dentist the following day to find out what the deal was. The dentist treated the area of the tooth for an infection and cleaned the gum line around the tooth after numbing the area. Apparently, I cracked the tooth and in the process, broke a blood vessel, which caused the swelling and discomfort. Thank goodness there was no infection, but to be on the safe side, I will continue the antibiotics. Since this occurred the roof of my mouth had a blister like swelling that was lanced to releive the pressure and build up of blood. Everything is fine and it reminded me how important it is to see my dentist on a regular schedule.
The blood clots are usually caused from a blunt trama to the teeth or gums. Possibly a reaction to metal, plastic, or a foreign body imbedded in the gums or tissue, but to be on the safe side, always consult your dentist and follow their instructions. It could be more serious than what happened to me.