What kind of infection would not be taken care of after two rounds of antibiotics?

Depends on variables: The best treatment for a given infection comes from taking the germ, identifying it in the lab, and testing it against various antibiotics to see which one works best.If not, the infection:may not be a bacteria, may be a bacteria that is not killed by the 2 meds chosen, the med may not reach adequate blood levels to kill the germ.Discuss the issue with your doc and see what other things can be done.

Nothing works : 100% of the time?If your still sick, return to your treating physician or get a 2nd opinion.The scope of this type of evaluation is much to broad to be addressed in this format.

See below: After a tooth extraction you could have a retained piece of root that would cause recurrent infections. Amoxicillin does not cover a number of bacteria involved in oral infections. Augmentin (amoxicillin and clavulanate) or Clindamycin might work better. Good luck.