We saw in the section on occlusions that each tooth consists of a molar and a root. The molar of the tooth - in a section - consists externally of enamel (it is the hardest substance of the human body), in between of dentin (it is the main substance of the tooth), while in the center is the pulp cavity. In fact, the first two constitute the hard dental tissues of the molar tooth, while the pulp cavity contains the soft tissues of the molar which are none other than the vessels and nerves of the tooth.

When caries develop in a tooth and it is not discovered in time to be cleaned and restored with the help of a filling, then the damage can reach, after affecting the entire depth of the hard dental tissues, the pulp cavity. As toxins and germs enter the pulp from the caries cavity, the pulp through its vessels sends more blood to the inside of the tooth in order to deal with the invaders. However, because the inside of the tooth has inflexible walls, unfortunately the blood, increasing the pressure in the pulp, strangles its vessels and nerves (which for this reason create a feeling of very intense pain), leading to necrosis of the tooth. The necrotic rachis tissues then form a substrate and further proliferation of microbes (pulp gangrene) which in turn cause additional pain in the nerve of the bleeding tooth. The process of necrosis is completed by complete necrosis of the pulpal nerve as well (although the pulpal nerve may remain in a necrotic state for several days). Then the germs start to exit from the end of the tooth root towards the jawbone, where they create an abscess (acute alveolar abscess).

In such a tooth, the only way to return to health is endodontic treatment. During this treatment, after opening the tooth and blocking the carious cavity, we then open the pulp chamber, so that with the use of special micro-tools we can start cleaning its interior. With the help of micro-tools and special chemical agents, we carefully clean the inside of the pulp of the tooth along the entire length of the root canal up to the end of its root. After the walls of the root canal are cleaned, shaped into the ideal shape and properly polished, we then place inside the special medicine that will help the body deal with any remaining microorganisms and heal the damage around the end of the tooth root. A few days later, we remove this medicine (calcium hydroxide) and after cleaning and drying the inside of the root canal again, we seal it permanently with a special glue and gutta-percha (rubber vulcanized with silver particles, so that it does not allow the growth of microbes). Because the quality and completeness of the occlusion is the main criterion for a good prognosis for the tooth, we always take care to choose the ideal occlusion technique (lateral condensation, vertical condensation, thermoplasticized gutta-percha) for each root canal, depending on its particular characteristics (how narrow , helical or bent is).

The above description corresponds to a typical endodontic treatment of a dead tooth. Apart from this case there are two more cases of endodontic treatment. The first case concerns endodontic treatment of a tooth during the preparation and treatment of a deep carious cavity. When, during the cleaning of the caries, extensive communication of the latter with the pulp cavity is revealed, the dentist decides on the immediate endodontic treatment of the tooth, as its necrosis is considered inevitable.

The second case is when a tooth needs to be ground extensively either to correct its axial tilt or to accommodate a telescopic crown. In this case there is talk of intentional endodontic treatment for prosthetic reasons.

A final category of need for endodontic treatment concerns teeth that have died for various reasons other than caries. Some of these reasons are rapid orthodontic movement, chronic periodontal trauma, end-periodontal lesions, tooth necrosis from excessive secondary dentin deposition, etc.

Finally, the need to repeat an endodontic treatment is not an unusual event, especially when the previous one does not meet the specifications of complete root canal occlusion in width and length. The most common consequence of an incomplete endodontic treatment and at the same time an indication of its repetition is the appearance of chronic periapical damage around the root of the tooth.

Finally, it is worth pointing out that an endodontically treated tooth has been deprived of both its nerve and blood vessels. It is the lack of the latter that makes the tooth increasingly dry over time. As you know, what is dry is also brittle. In order to avoid fractures in endodontically treated teeth, research has shown that they should be restored prosthetically (with a shaft and crown) in a short period of time after their endodontic treatment.