How is a root canal treatment performed?

How is a Root Canal Treatment Performed? Root canal treatment, or endodontic treatment, is a therapy that aims to restore a tooth affected by trauma or infection and whose pulp is irreversibly inflamed or necrotic.

Dental pulp is a living tissue located inside the tooth. Endodontic treatment is the technique used to remove this tissue and fill the inside of the tooth with an inert and biocompatible material.

For many people, this procedure is a somewhat mysterious thing. In this article, we want to give a simple and comprehensive explanation and eliminate any possible doubts about what root canal treatment is and how it is done.

How do you know if you need a root canal?

The first step is to identify if you need a root canal. Depending on the stage of the inflammatory process, common symptoms include intense pain, increased sensitivity to heat or cold, swelling around the affected tooth, or pain when chewing. Therefore, if any of these symptoms are present, it is important to consult a dentist as soon as possible. Above all, it is necessary to keep in mind that some cases can develop into dangerous infections. In this sense, to avoid surprises, the professional will perform a clinical examination, may request X-rays, and will evaluate your symptoms to make an accurate diagnosis.

Does root canal treatment hurt?

Before starting root canal treatment, the dentist will apply local anesthesia to ensure your comfort during the procedure. The anesthesia will make the area around the tooth insensitive to pain, ensuring a more tranquil experience. Certainly, there are cases that are more difficult to anesthetize due to anatomical factors and/or stages of the inflammatory process. But a good professional knows how to recognize such situations and address them correctly in order to greatly minimize discomfort.

How is a root canal treatment performed?

Step 1: Access to the pulp

Once the anesthesia has taken effect, the dentist will make a small hole in the crown of the affected tooth to access the pulp. This access hole is made from the back of the tooth, where it won't be visible when smiling. Therefore, in this first appointment, one of the goals is to eliminate all or part of the discomfort and pain the patient may be experiencing. Removing the inflamed pulp and purulent secretion will bring relief to the patient. The medication used inside the tooth between subsequent appointments also helps to further eliminate bacteria and combat the inflammatory process that causes the pain.

Step 2: Measuring the length of the tooth canal(s).

Yes, each tooth has a different size. And when a tooth has more than one root, each root has its own size.

Although we have already discovered and developed solutions for when this happens, professionals should take all precautions to prevent these accidents.

Using X-rays and electronic devices known as apex locators, the professional measures and determines these dimensions. If you wish to better understand the internal anatomy of the tooth, access the article. Dental Anatomy.

Step 3: Pulp removal and canal instrumentation.

After accessing the pulp, the dentist will carefully remove the infected or inflamed pulp using small, special instruments called endodontic files. During this process, constant irrigation of the canal with antimicrobial solutions and specific detergents eliminates any remaining residue or bacteria. This step is crucial to ensure complete disinfection of the canal.

In short, the action of the files inside the tooth cleans and reshapes the canal to allow for proper filling later.

Step 5: Root canal obturation

Once the canal is clean and free of infection, it will be filled with a biocompatible material, usually called a filling material. This material is typically a gutta-percha paste, which is inserted into the canal and sealed with dental cement to prevent reinfection.

Step 6: Temporary tooth restoration

After the dentist fills the root canal, the next step is to restore the tooth crown using a temporary filling. In some cases, it may be necessary to wait a few days for the treatment to completely eliminate the infection. Only then can the dentist finish with the permanent filling. This step concludes the root canal treatment.

And what happens after a root canal?

After the root canal treatment is complete, the dentist will replace the temporary filling with a permanent restoration, such as a crown or a filling. This step is essential to strengthen the remaining structure and reduce the risk of fracture or attack by caries-causing bacteria. This step is no longer part of the root canal therapy but rather the reconstruction of the tooth – the restoration.

The possible ways to restore this tooth depend on how much of the dental crown remains. It could be a simple restoration or a more complex solution requiring the fabrication of porcelain crowns, with or without internal reinforcement posts.

Are there cases where root canal treatment is unsuccessful?

Yes, there are cases where endodontic therapy may not be successful. Despite significant advances in the field of endodontics, several factors can contribute to an unsatisfactory outcome. Let's discuss some of the reasons why a root canal treatment might fail:

Anatomical factors associated with microbiological factors.

1. Complex anatomy or unexpected variations: Teeth have different anatomies, and in some cases, they may present complex root canals, bifurcations, or accessory canals that were not identified or treated during the procedure. If these structures are not properly cleaned and filled, they can harbor bacteria and lead to recurrence of infection.

2. Persistent infection: In some cases, the underlying infection may persist or spread to adjacent areas despite endodontic treatment. This can occur if it is not possible to completely eliminate the bacteria from the root canal system or if the infection spreads to the surrounding bone.

Inadequate technique

3. Inadequate sealing: Obturating the root canal with the appropriate material is a critical part of endodontic treatment. If we do not seal it correctly, leaks can occur, allowing bacteria to enter the root canal system.

4. Problems during the restoration stage: After endodontic treatment, the tooth must be restored with a crown or some other type of restoration. If this restoration is not done properly, the tooth may be vulnerable to fractures.

5. Tooth damage: During root canal treatment, it is possible that some damage may occur to the tooth, such as trepanation or perforation of the root. This type of accident can even permanently ruin the tooth.

Although we have already discovered and developed solutions for such cases, professionals should take all precautions to prevent these accidents. Thanks to new technologies developed in the last 20 years, this type of accident is rare.

Problems related to the patient's overall health.

6. Patient's systemic conditions: In some cases, the patient's health conditions, such as uncontrolled diabetes, compromised immune system, or underlying medical disorders, can affect the body's ability to fight infections, making root canal treatment less effective.

7. Reinfection: Even after successful treatment, teeth are still susceptible to future infections. If the patient does not maintain good oral hygiene or develops tooth decay in other parts of the tooth, this can lead to reinfection.

It is important to highlight that, even if a root canal treatment is initially unsuccessful, there are options to manage these cases, such as root canal retreatments, apical surgeries, and, in some cases, extractions followed by dental implants. Therefore, the choice of approach depends on the severity of the situation and the patient's specific conditions.

How is a root canal treatment performed?

Endodontic Retreatmento

If a root canal treatment fails, there is the possibility of trying again. But this situation has become increasingly rare. What I have observed over these 30 years is that the vast majority of indications for root canal retreatments have occurred in teeth with old root canal treatments, with techniques that are no longer used, or where the radiographic image showed an incomplete treatment that did not reach the end of the tooth.

Another possibility: the root canal obturation had filling defects in the lateral direction. An unsatisfactory, failed filling. This increases the risk of permeability, which could cause fluids or saliva to pass through, carrying bacteria back inside to the dental apex and consequently to the tissues around the root apex. To avoid these infections, the dentist must completely fill the inside of the canal with the material chosen for this purpose.

How is a root canal retreatment performed?

When performing a root canal retreatment, the first thing the endodontist does is remove the old filling. This is done using specific drills and solvents such as eucalyptol or orange oil, which soften the contents and facilitate their removal.

After removing this material, the dentist will perform almost all the steps of the root canal treatment already described in the first part of this article: measuring the length of the tooth, internal shaping, and new filling.

How is a root canal treatment performed?

Periapical surgery or apicoectomy with retrograde filling.

There is also a third possibility, which is becoming increasingly rare. There are cases where it is impossible to remove the filling from the tooth or reach the apex of the tooth through the root canal. For example, the tooth may have a cemented post supporting a single-unit prosthesis. In other words, this tooth may have a porcelain "pivot".

So, if there's an infection related to the root apex of that tooth, the solution is surgical. The surgeon then accesses that point, removes the tip of the tooth where the infection is located, and performs a retrograde filling with special materials. It's a somewhat complex procedure. Certain groups of teeth are so difficult to access that this surgery is simply not recommended. And with the increasing popularity of implants, the option of removing teeth in this condition and replacing them with implant-supported prostheses is becoming more and more common.

Eliminating fears

As you can see, there are several solutions to avoid losing a tooth. If you have a toothache, don't count on it stopping on its own. You're more likely to need help.

Don't be afraid. Root canal treatment is much more common than you think. People don't go around telling everyone what they went to the dentist for. Watch this illustrative video also.

Ask friends or other professionals for good references to choose the dentist who will handle your case.

Author: Nivaldo Pinho Gonçalves, Periodontist, CROSC 9696.

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