What Happens When A Tooth Dies?

It does not matter what actually causes a tooth to die, a patient usually feels little to no pain and will show no signs of an infection.  As the nerve of the tooth dies, toxins are released from the necrotic tissue.  Slow bone destruction is processed in the chronic state and an actual holding area or void will start to fill with material.  Toxins will then be picked up and carried throughout the body through the blood stream resulting in a slow death. 

Most patients won't know right away that damage done to a tooth will result in it's death.  Slowly the tooth will appear darker and a dental x-ray will show a void  or a dead pulp center chamber in the tooth.  Once this happens, the tooth is considered 'Abscessed'. Once a tooth with an abscess is removed you will usually find a cyst as the body created to try and contain the infection.

The picture on the right shows a tooth abscess and infected bulp.  The tooth decay began in the enamel of the tooth and spread to the pulp.

In an acute situation, no void or holding area exists large enough to accommodate the large quantity of purulent matter.
  If this is the case, the body will create an opening or drainage port to vent called a fistula.  Fistulas seen in the mouth are channels that will carry pus from the infected area to the outside of the face. A fistula can look like a pimple or a boil and allows access amount of puss to leave the body.  As gross as it is, without a fistula massive swelling in the face will occur.

By means of X-rays and clinical examinations, it is extremely difficult to ascertain changes in the dentin and the pulp when the severe morphological signs are not observable. You dentist will look at the x-ray for widening of the periodontal ligament surrounding the tooth, narrowing of canals, granulomas, cysts and condensing osteitis. Since energetic processes always precede the detectable morphological changes, an EAV test could be a great way to show the status of the pulp and dentin.