First off, like almost everyone else, I would suggest not doing it yourself. First, check around with local health department and any clinics or universities (worst case check some churches).
But if you insist on doing it yourself consider a few points:
1.) The pain, not only are you going to need pain killers for the wound but also the pain will probably be to intense for you to bear... so someone else will have to do it for you (enlist a friend)
2.) The severity of the wound caused: it is going to bleed profusely and it will have a large gaping wound unless you also close the thing back up yourself.
3.) Infection: you mouth is chock full-o-bacteria. It is one of the worst places to have a wound and it circulates close to your heart, so if you have a heart murmur or something else like me, a little bacteria in your blood stream can casue a lot of damage. Also sterilze any tools which you will use, don't just take a pair of pliers that are laying around and stick them in your mouth.
4.) Sub point from above, you will need antibitoic, not just over the counter, prescription antibiotic or an infection can spread and we are talking marjor damage which can result in losing a lot more of your mouth and sourounding tissue, and most likey a large bill form your local hospital. Also because you seem to be the type of person [rant] if you begin a prescription of antibiotics, finsh off the damn bottle as perscribed, don't just stop becasue you think you are better. and don't save a couple for a quick fix on a cold or flu for later. it is those people who do that which have created new antibiotic resistant strains[/rant]
Followup: Don't do it yourself. And by the way wehre do you live??