Sorry I wish I had seen this earlier. There are different types of dental abscess (an abscess is a collection of pus), the most common are due to a dead pulp/nerve caused by decay or trauma, and an infection associated with a partially erupted wisdom tooth. For the nerve related abscess the only real solution is removal of the cause of the infection (either by opening up the tooth, cleaning and filling the root canal or by removing the tooth), antibiotics work but only for a short period of time as the cause of infection remains. If you are stranded without access to a dentist then paracetamol/ibuprofen can help. Regarding the wisdom tooth infection, rinsing with hot salt mouthwash or 'Corsodyl' mouthwash, along with gentle brushing under/around the infected gum will help, but an antibiotic is usually required in addition tothis. This can be definitively successful if the tooth fully erupts but more often than not the problem will turn and the tooth is for the bin!
Hope this helps if you have future probs
Pedro