Root canal treatment: everything you need to know about this dental procedure

Root canal treatment is sometimes necessary when a cavity, an infection or an injury has reached the nerve at the core of the tooth. What's known in technical terms as endodontics makes it possible to keep the original tooth while eliminating the pain and the risk of complications.

Contrary to what you might hear, a root canal treatment is now done under local anesthesia and goes smoothly, without too much discomfort. Let's take a closer look at this procedure, which is actually quite common at the dentist's.

Quite simply, it means removing the pulp, the tissue right at the centre that houses the nerves and blood vessels. Also called endodontic treatment, dentists perform it when this pulp is genuinely damaged, due to several possible causes. Once the root canals have been thoroughly cleaned and disinfected, they're sealed to save the tooth.

Once treated, the tooth no longer has any living tissue inside. It then no longer feels hot, cold, or even pain.

That's why people talk about a “dead tooth”. In reality, it still holds firmly in the bone thanks to the ligament surrounding it, and it keeps doing its job. It stays functional, but over time it usually becomes more fragile. The dentist sometimes recommends protecting it with a crown.

If a lesion isn't treated in time, it can work its way through the enamel, then the dentin, and end up reaching the core of the tooth. When bacteria settle in this area full of nerves and blood vessels, it causes pulpitis.

At this stage, the discomfort often gets worse, especially with hot or cold or when chewing. If the damage is too advanced, a simple filling or a rebuild is no longer enough: a root canal treatment becomes necessary.

A bacterial infection can also develop inside the tooth or at the tip of the root. It can lead to a dental abscess, often with significant pain, swollen gums or sensitivity to pressure.

In that case, root canal treatment makes it possible to thoroughly clean the canals and remove the source of the dental problem.

A violent blow to a tooth, from a fall, an accident or sport, can damage the nerves, even if the tooth looks intact from the outside. Sometimes, the pulp stops being properly supplied with blood and ends up dying off.

The pain can be triggered by cold, heat, or even without any obvious reason. When examinations show that the nerve tissue is affected and no conservative solution really relieves the patient, root canal treatment may be the best option to regain everyday comfort.

Root canal treatment is done under local anesthesia, so fortunately you won't feel a thing. The dentist first opens a small access point to reach the inside of the tooth. They then remove everything that's infected or inflamed, then carefully clean and disinfect the root canals.

Once everything is nicely clean, they fill it with a special material to keep the issue from coming back. Finally, they rebuild the tooth with a composite, an inlay-onlay or a crown, depending on its condition.

It mostly depends on the tooth. An incisor, with a single root, is often quicker to treat than a molar with several canals. This type of treatment is usually done in a single 45-minute to 1.5-hour session. But if the abscess is severe or the situation more complex, you may need to come back several times.

With today's anesthetics, a root canal treatment is barely painful. During the procedure, you may feel some pressure or manipulation, but no sharp pain. If that bothers you, the dentist can adjust the anesthesia to make you more comfortable.

There may be some mild sensitivity in the days that follow: this is the tissue around the root healing. Some people feel discomfort when chewing or sensitivity to pressure for a few days, and then it gradually settles down.

On the other hand, if you have a sharp throbbing pain that persists, or swelling, you should see someone quickly to check there's no complication.

It no longer receives blood through the pulp vessels. It keeps on chewing, but over time it becomes more fragile.

This fragility mostly comes from the loss of tooth structure. Back teeth, like molars, are especially prone to cracks or fractures because they take on so much force during chewing.

After a root canal treatment, the dentist may suggest a suitable restoration to strengthen the tooth and give it a longer lifespan.

Depending on how much tooth structure remains, this protection can be a composite, an inlay-onlay or a crown. The latter is often the most common choice for heavily weakened molars. And even though the tooth no longer has a nerve, you still need to keep up a good routine. Because your tooth can still develop a cavity or show gum problems.

Sometimes bacteria remain in the canals after the procedure, or reappear due to a leak.

This can lead to inflammation or an infection at the root. Pain, sensitivity when chewing, or even an abscess can appear months or years after the root canal treatment.

In that case, a root canal retreatment may be needed to get rid of it once and for all.

Even when well treated, this tooth remains more vulnerable to fractures than a living tooth. The fragility gets worse if it has lost a lot of structure, and a fracture can sometimes threaten its survival and require further treatment.

Endodontic treatments have a good success rate, but no medical procedure is guaranteed 100%. The complexity of certain roots, canals that are hard to access, or a very widespread infection can limit the effectiveness of the initial treatment.

If the root canal treatment fails, several options exist: retreating the root canals, endodontic surgery, or, in the most complicated cases, extracting the tooth.

When pulp damage is detected early enough, it's sometimes possible to avoid this procedure. The dentist then favours treatments aimed at preserving its vitality.

Depending on the situation, this might involve treating a cavity, pulp protection or a pulp cap, aimed at preserving the nerve when it hasn't been irreversibly damaged. Hence the importance of seeing a dentist quickly in case of persistent discomfort or sensitivity.

When the tooth is too damaged, fractured, or the inflammation can no longer be controlled, extraction may become the only remaining option. This solution still remains a last resort.

After an extraction, replacement with an implant, a bridge or a denture may be needed to prevent the neighbouring teeth from shifting.

Most patients dread the root canal treatment before their appointment. Yet many find it less uncomfortable than they expected.

Reviews often report a clear drop in sensitivity within days of treatment, especially when the tooth was infected or badly inflamed beforehand. That said, the experience varies from person to person depending on how complex the procedure was, the level of anxiety, or the tooth's initial condition.

Endodontic treatments now have a high success rate when carried out under good conditions and combined with regular follow-up.

Several studies estimate that more than 85 to 95% of properly root-canaled teeth are still functional many years after this kind of treatment. It thus helps avoid many extractions and contributes to preserving natural teeth for the long term.