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Cleaning of tooth canals: how it is carried out, consequences, what is done afterwards
Last reviewed: 04.07.2025
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Root canal cleaning is a dental procedure that is performed when an infection gets into the root canals. This procedure can have different implementation options depending on the diagnosis, anatomical features of the root canals and the general somatic status of the body. If you are facing this treatment, you need to be prepared for the fact that this process is not quick and most often lasts from two to ten visits.
Indications for the procedure
Indications for root canal cleaning are acute and chronic pulpitis and periodontitis. Pulpitis is an inflammation of the vascular-nerve bundle of the tooth, which is located in the root canals. This disease can occur as a complication of caries or be the result of a tooth injury. If a complication of the carious process occurs, the infection gets into the pulp chamber, where an inflammatory process soon occurs. This response of the body is aimed at destroying the infection in the cavity of the tooth. However, side effects of a severe inflammatory process can be the appearance of pus in the pulp cavity. Purulent exudate spreads to the surrounding hard tissues, and can also penetrate beyond the apex of the root canal. In this case, we are talking about periodontitis, which is also accompanied by the release of purulent contents. In the presence of an inflammatory process in the periodontal tissues, root canal cleaning is extremely necessary. And if you do not seek help in time, the disease can become chronic.
Although a tooth injury is not an infectious process, like the previous diseases, it may also require cleaning the tooth canals. When the integrity of the tooth structures is damaged, pathogenic microorganisms penetrate the pulp tissues through damaged areas of hard tissues and provoke the occurrence of inflammatory processes. Another factor in the infection is a metabolic disorder in damaged dental structures. The fact is that when the periodontium is injured, it is damaged, which disrupts the stability of metabolism. Thus, the body tries to compensate for these disruptions in the periodontium, which causes a weakening of the protective factors. This leads to the fact that the infection present nearby begins to actively live and spread to neighboring areas.
Technique canal cleaning
The technique of cleaning the canals is a series of sequential manipulations using endodontic instruments. After removing the affected tissues of the tooth, the doctor begins to extract the pulp and clean the root canals from the remains of the affected tissues. Before each manipulation, it is important to rinse the tooth cavity with antiseptic solutions to reduce the spread of infection. The next stage is cleaning the walls of the canals with cutting instruments that remove infected dentin and give the canal the desired shape. The correct bend and taper of the root canal play an important role at the filling stage. After mechanical instrumentation, the root canals are treated with aggressive antiseptics, dried and filled. At key stages of treatment, the dentist must control the position of the instrument in the canal using an apex locator or X-ray. An apex locator is a device that shows the location of the instrument in the root canal. This point is very important, since without visual control there is a risk of the cutting instrument advancing beyond the apex of the root, and when treating periodontitis there is a possibility of the material being removed beyond the apical opening (the apex of the root).
Open tooth after root canal treatment
After the above manipulations, the further therapeutic plan may be different. If the treatment was carried out for pulpitis, then after cleaning the root canals, they are usually filled and the tooth is restored. As for filling the canals, this manipulation can be carried out using various methods. Sometimes filling materials are used without any supporting structures. If the tooth requires more reliable restoration, then a combination of composites and pins can be used. If the tooth crown is badly damaged, it is proposed to install a cast metal inlay (an intracanal microprosthesis on which the crown is installed). If the treatment was carried out for periodontitis, the treatment tactics will be completely different. After cleaning, the canals are left open for 1-2 days to create an outflow of purulent contents. The extraction of pus is accelerated by rinsing, which the patient regularly does. During meals, it is recommended to cover the open tooth with a cotton ball, and after meals - actively rinse with warm antiseptic solutions. And only after the symptoms of periodontitis have subsided do they begin temporary and then permanent filling of the canals.
Cleaning the canals of a wisdom tooth
Cleaning the canals in a wisdom tooth is carried out according to standard rules, but there are a number of difficulties in performing the task. The root canals in a wisdom tooth often have many branches and are very curved, which makes it difficult to carry out their mechanical treatment. Also, wisdom teeth can be tilted in different directions, which creates difficult conditions for working with their root canals. Large strands of mucous membrane and the inability to open the mouth wide interfere with the doctor in working with these teeth. In addition to the listed nuances, it should be remembered that the root system of the eighth teeth often passes through the mandibular canal. This is a canal in the bone of the lower jaw, which contains the mandibular nerve. It innervates all the teeth of the lower jaw, as well as some areas of the skin of the face, the mucous membrane of the gum, muscles and tongue. Damage to this nerve entails a violation of the innervation of these areas, and when treating the canals of a wisdom tooth, such a danger exists.
Despite all the described troubles that a doctor encounters when treating root canals of wisdom teeth, it is quite possible to perform high-quality treatment. To do this, a doctor must have theoretical knowledge, practical experience and the necessary set of high-quality tools.
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Tooth nerve removal and root canal cleaning
To perform high-quality pulpitis treatment, the doctor needs to remove the nerve and clean the tooth canals. This is necessary to eliminate the infectious inflammatory process. Before starting treatment, the doctor decides on the choice of treatment method. Among them, there are vital and devital methods. The essence of the first method is that the pulp (nerve) is removed alive. Preliminary drug preparation and anesthesia are carried out in the area of the diseased tooth. Then the tooth nerve is removed and the root canals are cleaned. The second method is the removal of the pulp with preliminary devitalization. This method is longer and includes a number of visits. At the beginning of the treatment, a devitalizing substance (arsenic or paraformaldehyde) is left in the tooth and after a certain time (from 2 to 7 days) the nerve is removed. In modern dentistry, the first method is most often used due to its speed and less pain.
Contraindications to the procedure
There are no absolute contraindications to root canal cleaning. There are only contraindications to specific methods of pulpitis treatment, namely the vital method. First of all, we are talking about severe stages of general somatic pathologies (for example, hypertension of 2-3 degrees, uncompensated diabetes mellitus, hepatitis, etc.). Also, allergic reactions to anesthetics should be included in this group, since in this case it is impossible to perform tooth anesthesia.
In case of unstable mental state or mental illnesses, it is not recommended to carry out treatment with the vital method. In case of severe pathologies of the nervous system, treatment under anesthesia may be necessary.
One of the main reasons why this type of therapy is not used is the anatomical features of the canal structure. If they have a curved shape, then it will be very difficult to treat such a canal. Your doctor should always understand whether he or she will be able to perform high-quality treatment of this tooth. If you leave scraps of nerve in the canal or do not completely fill the canals, then there is a risk of various complications.
Often the vital method is not used in elderly people. Most often this is due to the fact that anesthetics contain vasoconstrictors. With the instability of the cardiovascular system of elderly people, painkillers can cause serious damage to the body.
As stated above, all the listed contraindications are only relative. This is due to the fact that in modern dentistry there are hypoallergenic forms of anesthetics, drugs with a minimum dose of vasoconstrictors. Also, creating comfortable conditions for the patient, the work of the doctor with an assistant allows you to perform all manipulations as quickly and efficiently as possible.
Consequences after the procedure
Toothache after root canal cleaning can indicate many conditions. The most common is a complication of the disease for which treatment was carried out. Incorrectly treated pulpitis can develop into periodontitis, and acute periodontitis can develop into a chronic form.
Why does a tooth hurt after root canal treatment?
When treating pulpitis, it is very important that affected tissues, aggressive antiseptic solutions and other substances are not removed beyond the apex of the root canal. Due to the fact that the canal in the apex area narrows very much, the gap between it and the periodontal gap remains very small. It is called the apical foramen. If the dentist widens it, the treatment may be ineffective, since the inflammatory process will spread to the periodontal tissues.
If acute periodontitis or pulpitis has been treated, chronic periodontitis may develop after some time. The reasons for these outcomes are not always clear, sometimes it is banal hypothermia and a decrease in the body's defenses. In some cases, the cause is increased stress on the tooth. And sometimes complications arise due to incomplete removal of infection from the canals. Regardless of the cause of the complication, it is necessary to immediately contact a specialist who can stop the spread of the inflammatory process.
If after root canal cleaning the tooth hurts when you press on it or on the gum, this may indicate the development of periodontitis or a relapse of a chronic disease. With periodontitis, purulent exudate accumulates in the periodontal gap and puts pressure on the tooth. Symptomatically, this may manifest as a feeling of an "overgrown tooth". In this case, there will be constant pulsating pain, especially when biting on this tooth.
If there is pain when pressing on the gum near a previously treated tooth, then most often the cause is chronic periodontitis, or periodontitis. With chronic periodontitis, a large amount of pus accumulates in the periodontium, which forces it to look for ways out. As a rule, pus moves towards the gum from the lips and cheeks. This is explained by the fact that the bone of the socket on the buccal side is thinner than on the palatine side. Therefore, pus makes a channel in the bone and gum, "eating away" hard and soft tissues. This process is accompanied by reddening of the gum, sharp pain when touching it. As a result of the release of pus, a small hole (fistula) is formed on the gum, through which the contents flow into the oral cavity. The presence of a fistula is one of the most obvious signs of exacerbation of chronic periodontitis.
Sometimes the cause of pain when pressing on the gum in the area of the treated tooth is periodontitis. Periodontitis is an inflammation of the tooth ligament, during the progression of which the bone around the tooth is destroyed. As a result of this chronic process, the tooth gradually begins to loosen and eventually falls out. In this case, to confirm the diagnosis, you need to take an X-ray, as well as a number of studies that are performed in a dental clinic.
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How long does a tooth hurt after root canal treatment?
After cleaning the tooth canals, there should be no pronounced pain. There may be unpleasant sensations in the tooth, slight tingling, the tooth may be hypersensitive. Sensitivity when biting on the treated tooth for up to two to three weeks is considered normal. This is due to the fact that after the nerve is removed, some of the nerve fibers remain behind the apical opening. Due to recent treatment, the remaining nerves are in a stressed and irritated state. Therefore, even minor chewing load, eating hot and cold food, can provoke unpleasant sensations. However, you should be attentive to your body! If the pain is constant, pulsating, tearing, the duration of which is more than two weeks - this is a clear reason to contact a specialist.
Complications after the procedure
Due to the complexity and duration of root canal treatment, some complications may develop. They may be related to the doctor's inexperience, lack of technical equipment, missed visits by the patient, etc. As a result, the infectious process spreads to neighboring areas and causes various diseases.
The most common complication after root canal cleaning is residual pulpitis and periodontitis. These diseases occur after incomplete extraction of pulp from the root canal or ineffective treatment of the inflammatory disease. As a result, constant pain is felt in the tooth, which can last for several weeks and months. The only way out in this case is repeated root canal cleaning, which will allow you to extract all the affected tissues and stop the inflammatory process.
In cases where the body's immune system is weakened, residual periodontitis can quickly develop into periostitis. Periostitis is an inflammation of the periosteum in the tooth area, commonly known as gumboil. Its main symptoms are: symptoms of intoxication (headache, weakness, elevated body temperature), swelling in the cheek area, soreness of the skin in the area of swelling. If your cheek is swollen after cleaning the root canals, you must immediately see a doctor. Even if your doctor is on vacation, on a business trip, or is absent from work for other reasons, you must urgently seek dental care. In this case, it does not matter at all which clinic to visit. The main thing is to do it as quickly as possible. If you do not perform surgery in time and do not undergo a course of anti-inflammatory therapy, this disease can be complicated by more serious conditions.
If inflammatory processes are not stopped in time, acute or chronic osteomyelitis may develop. This disease can be described as inflammation of bone tissue. This pathological process, severe in its course and often with an unfavorable prognosis, can lead to a violation of the integrity of bone tissue, the formation of bone defects that disrupt the functional and anatomical integrity of the hard tissues of the oral cavity. This condition is rare, and usually occurs in people who lead a disorderly lifestyle.
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The prognosis after root canal cleaning is usually favorable. A well-treated tooth serves for years and does not cause any complaints. A competent doctor and a conscientious patient together can achieve colossal results in complex treatment. People's reviews about root canal cleaning vary. Some consider this method ineffective and useless. However, high-quality root canal cleaning allows you to keep your tooth in working condition for many years. Be healthy!