When bacteria (germs) enter your Tooth through deep cavities, Cracks or Broken/Fractured Fillings, your Tooth becomes painful, Infected and Abscessed. An abscessed tooth is a tooth with an infection in the pulp. If pulp becomes infected, it needs to be removed. An abscessed tooth may cause pain and/or swelling. The infection can be identified from the complaints, oral examination and from a Dental x-ray.