Hi XXXXXXXXX~
Unfortunately without seeing your dog and having a 'real life' realtionship with him, none of the experts here would be able to tell you which antibiotics to use and at what dose. The reason we can't is because it's against the law to prescribe medication without an in person relationship.
That being said, I can tell you that if it were my dog, and he were in good general health, I could give 1/2 of a low dose or children's aspirin for the pain once every 12 hours or so...however, you can't give it for more than 3 days without consulting your regular vet. Also, you should give it with a little food, so you don't upset his stomach.
If this is a dental issue, you should probably take him in to the emergency clinic in your area. Although they won't be able to pull the tooth (most emergency clinics don't do dental work), they will be able to send out the antibiotics that your dog would likely be placed on before your regular vet would pull the tooth anyway (most vets will put a dog on a few days of something like Clavamox before dealing with an infected tooth...this is to help keep that infection from getting into the bloodstream and causing a system-wide infection known as sepsis).
I hope this helps.
Certified Veterinary Technician
Associates Degree in Veterinary Technology. State and Nationally certified.
Thanks for the info.