Root Canal Process Step by Step: What Happens During Treatment

A root canal removes infected tissue from inside your tooth, cleans the canal system, and seals it to prevent reinfection. The procedure typically takes 30 to 90 minutes. Understanding each step can help reduce anxiety and prepare you for what to expect at your appointment.

8 min readMedically reviewed contentLast updated March 20, 2026

Key Takeaways

  • A root canal involves 9 main steps: X-ray, anesthesia, rubber dam, access opening, pulp removal, cleaning and shaping, filling the canals, temporary restoration, and permanent crown.
  • You should not feel pain during the procedure. The tooth is fully numbed before treatment begins, and your endodontist will confirm you are comfortable before proceeding.
  • Most root canals are completed in a single appointment lasting 30 to 90 minutes, depending on the tooth.
  • The endodontist uses a dental microscope and electronic instruments to clean and shape canals that are thinner than a human hair.
  • A crown placed after root canal treatment protects the tooth from fracture and restores full chewing function.
  • Mild soreness for a few days after treatment is normal. Severe or worsening pain is not normal and should be reported to your endodontist.

Before the Root Canal: Diagnosis and Planning

The root canal process begins before any instruments touch your tooth. Your endodontist needs to confirm which tooth is the problem, assess the complexity of its canal system, and develop a treatment plan.

Step 1: X-Rays and Diagnosis

Your endodontist takes X-rays to see the shape and length of the root canals and to check for infection in the surrounding bone. In many endodontic offices, a CBCT scan (a three-dimensional X-ray) provides a detailed 3D view of the tooth. This reveals the exact number of canals, their curvature, and any unusual anatomy.

The endodontist also performs diagnostic tests. These may include tapping on the tooth, applying cold to individual teeth, or pressing on the gum to identify the source of pain. These tests help confirm which tooth needs treatment and whether the pulp is inflamed or dead.

What You Feel During Diagnosis

The cold test may produce a brief, sharp sensation on healthy teeth and a different response on the problem tooth. Tapping on the infected tooth may cause a dull ache. These tests are brief and help your endodontist pinpoint the issue accurately.

Step 2: Numbing the Tooth (Anesthesia)

Before treatment begins, the endodontist administers local anesthesia to numb the tooth and the surrounding area completely. A topical numbing gel is applied to the gum first to minimize the sensation of the injection.

For most teeth, the area is fully numb within 5 to 10 minutes. Endodontists are specialists in dental anesthesia and have additional techniques for teeth that are difficult to numb, such as lower molars with active infections. If you feel any sensation during the procedure, tell your endodontist immediately. Additional anesthesia can be given at any time.

What You Feel

You will feel pressure from the injection but the topical gel reduces the sharpness. Within minutes, the tooth, gum, and surrounding area go numb. You may feel a sense of heaviness or tingling in your lip, cheek, or tongue. This is normal and means the anesthesia is working.

Step 3: Placing the Rubber Dam

A thin sheet of rubber or vinyl, called a dental dam, is placed over the tooth being treated. A small hole in the dam fits over the tooth, isolating it from the rest of the mouth. The dam is held in place with a small clamp on the tooth.

The rubber dam serves two purposes. It keeps saliva and bacteria from the mouth out of the open tooth during treatment. It also prevents the small instruments and irrigation solutions used during the procedure from entering your throat. You can breathe normally through your nose and around the dam.

What You Feel

You will feel the clamp being placed on the tooth, which produces mild pressure. Since the tooth is already numb, this is not painful. The dam may feel unfamiliar at first, but most patients adjust to it within a minute or two.

Step 4: Creating the Access Opening

The endodontist uses a small dental drill to create an opening through the top (biting surface) of the tooth. For front teeth, the opening is made on the back surface. This opening provides access to the pulp chamber and the canal system inside the tooth.

The endodontist works under a dental microscope that magnifies the inside of the tooth up to 25 times. This level of magnification allows precise removal of decay and accurate identification of each canal opening.

What You Feel

You will feel vibration from the drill and water spray used to cool the tooth. You should not feel pain. If you feel anything sharp or uncomfortable, raise your hand and the endodontist will stop and administer more anesthesia.

Step 5: Removing the Infected Pulp

Using small, flexible instruments called files, the endodontist removes the infected or damaged pulp tissue from the pulp chamber and the root canals. The pulp contains the tooth's nerve, blood vessels, and connective tissue. Once removed, the tooth no longer feels hot or cold, but it remains functional because the surrounding tissues continue to nourish the outer tooth structure.

This step effectively eliminates the source of infection and pain. The bacteria and debris are flushed out with irrigating solutions.

What You Feel

You should not feel pain during pulp removal because the tooth is numb. You may feel slight pressure or movement as the files work inside the tooth. Some patients hear a faint scraping or clicking sound from the instruments.

Step 6: Cleaning and Shaping the Canals

After the pulp is removed, the endodontist cleans and shapes each canal using progressively larger files. This step removes any remaining tissue, bacteria, and debris from the canal walls. The canals are shaped into a smooth, tapered cone that can be sealed effectively.

During cleaning, the endodontist flushes the canals repeatedly with sodium hypochlorite (a disinfecting solution) and other irrigants. An electronic apex locator measures the exact length of each canal to ensure the instruments reach the tip of the root without going beyond it.

This is typically the longest step of the procedure. Root canals in front teeth have one canal and take less time. Molars can have three to four canals, some of which curve or branch, requiring more time and precision.

What You Feel

You will feel pressure and occasional vibration as instruments move inside the canals. You may taste or smell the irrigating solution slightly, which has a mild bleach-like quality. The rubber dam prevents you from swallowing it. This step can take 15 to 45 minutes depending on the number and complexity of canals.

Step 7: Filling the Canals

Once the canals are clean, dry, and shaped, the endodontist fills them with a biocompatible rubber-like material called gutta-percha. The gutta-percha is heated and compressed into the canal to create a tight seal from the tip of the root to the access opening. A sealer cement is used alongside the gutta-percha to fill any microscopic gaps.

The goal of this step is to create an airtight seal that prevents bacteria from re-entering the canal system. A well-sealed root canal is the foundation for the long-term success of the treated tooth.

What You Feel

You may feel warmth as the gutta-percha is heated and a sense of pressure as it is compressed into the canals. This step is brief and typically not uncomfortable.

Step 8: Placing a Temporary Restoration

After the canals are filled, the endodontist places a temporary filling in the access opening to seal the tooth between your endodontic appointment and your crown appointment. This temporary material protects the inside of the tooth from bacteria and food particles.

The temporary filling is not designed to last long-term. You should schedule your crown appointment within 2 to 4 weeks. Until then, avoid chewing hard or sticky foods on the treated tooth.

What You Feel

Placing the temporary filling feels similar to having a regular filling placed. You may feel pressure and tapping as the material is packed into the opening. At this point, the procedure is essentially complete.

Step 9: Permanent Crown (Separate Appointment)

The final step in the root canal process is a permanent crown or restoration, placed by your general dentist or a prosthodontist at a separate appointment. A crown covers the entire tooth, providing strength and protection against fracture.

Root canal-treated teeth become more brittle over time because they no longer receive blood supply from the pulp. A crown distributes chewing forces across the tooth and significantly reduces the risk of the tooth cracking. For back teeth (premolars and molars), a crown is strongly recommended. For front teeth, your dentist may recommend a crown or a bonded filling depending on how much tooth structure remains.

Crown Cost and Timeline

A dental crown typically costs $800 to $1,500. Most dental insurance plans cover crowns at 50% after the deductible. The crown appointment usually takes 1 to 2 visits: one to prepare the tooth and take impressions, and another to place the finished crown. Some offices offer same-day crowns using digital milling technology.

Recovery After a Root Canal

Most patients can return to normal activities the same day. The anesthesia wears off in 2 to 4 hours. Here is what to expect as you heal.

The First Few Days

Mild soreness or tenderness around the treated tooth is normal for 2 to 5 days. This is inflammation in the tissues around the root tip, not a sign of failure. Over-the-counter ibuprofen or acetaminophen manages this discomfort effectively for most patients. Avoid chewing on the treated side until the permanent crown is placed.

When to Call Your Endodontist

Contact your endodontist if pain worsens instead of improving after 2-3 days, if swelling develops or increases, if the temporary filling falls out, if you develop a fever, or if you have an allergic reaction to prescribed medication. These situations are uncommon but require prompt attention.

Root Canal Cost and Insurance

The cost of a root canal depends on which tooth is treated. Front teeth with a single canal are the least expensive. Molars with multiple canals cost more. Costs vary by location and provider.

Typical cost ranges for the root canal procedure itself (not including the crown): front teeth cost $700 to $1,000, premolars cost $800 to $1,200, and molars cost $1,000 to $1,500. An endodontist may charge slightly more than a general dentist, reflecting their specialized training and equipment.

Most dental insurance plans cover root canal treatment at 50-80% after the deductible. The crown is covered separately, also typically at 50%. Verify your coverage before treatment. Many endodontists offer payment plans or accept third-party financing.

When to See an Endodontist

An endodontist is a dentist with 2 to 3 years of additional training focused on diagnosing and treating problems inside the tooth. Endodontists perform root canals daily and use specialized equipment, including surgical microscopes and 3D imaging, that most general dental offices do not have.

You should consider seeing an endodontist if the tooth has complex anatomy (curved or narrow canals), if this is a retreatment of a previous root canal, if your general dentist refers you, or if you have significant dental anxiety and want a specialist who performs this procedure routinely.

Find an Endodontist Near You

Every endodontist on My Specialty Dentist has verified specialty credentials. Search by location to find endodontists in your area who perform root canal treatment.

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Frequently Asked Questions

Does a root canal hurt?

The tooth is completely numbed before the procedure begins. Most patients report feeling pressure but not pain during treatment. The experience is similar to having a filling placed, though it takes longer. Endodontists are specialists in dental anesthesia and have techniques for teeth that are difficult to numb.

How long does a root canal take?

A root canal on a front tooth typically takes 30 to 45 minutes. A premolar takes 45 to 60 minutes. A molar with multiple canals takes 60 to 90 minutes. Most root canals are completed in a single visit. Complex cases, such as retreatments or teeth with unusual anatomy, may require a second appointment.

Can I eat after a root canal?

Wait until the anesthesia wears off before eating to avoid biting your cheek or tongue. Once numbness resolves (2-4 hours), you can eat soft foods. Avoid chewing on the treated side until the permanent crown is placed, as the temporary filling is not designed for heavy chewing forces.

How long does it take to recover from a root canal?

Most patients feel mild soreness for 2 to 5 days, manageable with over-the-counter pain relievers. Most people return to work or normal activities the same day or the next day. Full healing of the tissues around the root tip takes a few weeks to a few months.

Do I always need a crown after a root canal?

A crown is strongly recommended for premolars and molars after root canal treatment because these teeth bear heavy chewing forces and become more brittle without a blood supply. Front teeth may be restored with a bonded filling instead of a crown if enough natural tooth structure remains. Your dentist or prosthodontist will advise based on your specific situation.

What happens if I delay getting a root canal?

An infected tooth will not heal on its own. Delaying treatment allows the infection to spread to the surrounding bone, which can lead to abscess formation, bone loss, and eventually tooth loss. In severe cases, the infection can spread to other areas of the head and neck. Prompt treatment gives the tooth the best chance of long-term survival.

Sources

  1. 1.American Association of Endodontists. "Root Canal Treatment." AAE Patient Education.
  2. 2.Ng YL, et al. "A prospective study of the factors affecting outcomes of non-surgical root canal treatment." Int Endod J. 2011;44(7):583-609.
  3. 3.Salehrabi R, Rotstein I. "Endodontic treatment outcomes in a large patient population in the USA." J Endod. 2004;30(12):846-850.
  4. 4.American Dental Association. "Root Canals." ADA MouthHealthy.
  5. 5.Siqueira JF Jr, Rocas IN. "Clinical implications and microbiology of bacterial persistence after treatment procedures." J Endod. 2008;34(11):1291-1301.

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