Dental pulp is a high specialized tissue located inside the hard tissue of the tooth made of veins, arteries, nerves and connective cells. After a deep caries, or a trauma, the pulp undergoes to changes that usually start with an inflammation: the pulpitis, a often very painful condition, that if contaminated by bacteria, can cause infection and even necrosis.
The infection, if not treated, can spread rapidly out of the root apex to the surrounding bone, where the bacteria can cause lesion, abscess or dental granuloma (which can evolve in cyst) that are evident under the x-ray as dark area close to the root apex (Fig.2/3). The use of antibiotics or anti-inflammatory it is not solving the problem as inside the tooth the flux of blood is very little or sometimes inexistent.
In these cases the only alternative to the tooth extraction is the endodontic treatment (treatment of the canal). Another indication for the endodontic treatment is the re-treatment of previous treatment that were not successful and do not guarantee the complete seal of the radicolar canals to the bacterial or still have presence of necrotic pulp.