Endodontics is the branch of dentistry that studies specifically root canal therapy. Endodontic therapy brings to mind the root canal treatment. The most feared treatment among dental treatments is usually the root canal therapy. Today, root canal therapy is virtually painless and is completed in vital teeth in one session and in devitalized teeth it is completed usually in two sessions.
Any part of a tooth that is visible in the mouth is called “Crown”; the part of a tooth that exists in the bone is called “Root”. A tooth consists of several layers. The outer part of a tooth, meaning the part seen in mouth, is called enamel. Enamel is one of the most rigid tissues of our body. The root of a tooth is covered by a layer called cementum. Dentin layer exists under enamel and cementum. Dentin has the largest volume among all dental tissues and unlike enamel, dentin contains nerve ends. Due to this characteristic, it plays a role in the pain mechanism.
Pulp exists under dentin layer. The pulp contains nerves and vessels, and it plays a significant role in the eruption and the development of a tooth. The pulp also reflects the problems of tooth via the pain mechanism even after tooth eruption.
How do teeth get infected?
Bacteria exist in every person’s oral cavity. These bacteria do not cause harm under normal conditions. Bacteria produce acids from the food we consume and unless these acids are eliminated, acids damage the enamel consequently leading to caries in enamel tissue. Caries left untreated in enamel progress to the dentinal tissue. Though the dentin tissue warns through inducing pain, if the caries is left untreated, then microorganisms move towards the pulp. The pulp uses various ways to protect itself. One of them is through the pain mechanism. But if the invaded tooth is still not treated, after a while, microorganisms damage the vessels and nerves in the pulp, thus an infection is caused.
Trauma is another factor leading to infection. A blow might cause ruptures of vessels and nerves that enter a tooth through root apex, consequently leading to devitalisation. Addition of microorganisms in any way causes the infection of pulp.
Another cause of a pulp infection is an existent periodontal disease (disease of the gums and surrounding tissues of a tooth) for a long period of time.
How is an infected tooth determined?
Sensitivity and pain due to cold or hot food/drink and pain induced by eating might indicate an existent infection or the beginning of an infection. Apparent color changes might also be regarded as an infection symptom. In teeth with untreated caries extending to pulp, the infection might spread to jawbone from the apex of the root and might cause small or serious swelling. In such conditions, antibiotic use is appropriate along with dental procedures. The general opinion is that after the swelling is gone, the responsible tooth needs to be extracted. But this opinion is from the past. Even a tooth causing serious infections can be kept in the mouth by root canal therapy and it can serve for many years like any adjacent healthy tooth.
Stages of a root canal therapy:
1 - Determining the infected teeth through radiography.
2 - Removing the sensitivity of the tooth and its surrounding tissues by local anesthesia if the tooth is vital.
3 - Removal of caries in enamel and dentinal tissues and preparation of a cavity for accessing pulp.
4 - Isolation of the tooth by use of a rubber dam.
5 - Determination of the length of the canals by using electronic instruments and confirmation through radiography.
6 - Elimination of infected dentinal tissue along with microorganisms in the root canals by rotary endodontic instruments.
7 - Elimination of microorganisms with root canal disinfectants during rotary endodontic instrument use.
8 - If the tooth was not vital at the beginning of the treatment, a canal antiseptic is sealed into the canals for a period of time and then the canals are obstructed with canal fillings permanently.
9 - The purpose of the root canal treatment is to prevent the infection from reoccurring and to restore the damage by ceasing the relation between the tooth and its surroundings.
Subsequent to root canal therapy, particularly the treatment of vital teeth, tolerable pain or sensitivity induced by pressure on the tooth for a few days is possible. This is not uncommon and the pain will disappear in a short time.