Consult your dentist about a low profile mouth guard. For the most part they are fairly inexpensive and do offer a decent amount of protection. Unfortunetly it may take a while getting used to being able to talk properly with one. Other options are shemagh, neoprene face protector and full paintball mask. I suppose you could always look into getting a sykes face mask or some form of scary looking Army of two style mask.
"Its only a little bit on fire"