Root canal procedure step by step: what happens

Hearing that you need a root canal can make you nervous, often because you do not know what will happen in the chair. Knowing the root canal procedure step by step takes away much of that uncertainty. Root canal treatment removes the inflamed or infected pulp from inside a tooth, cleans and seals the root canals, and lets you keep the tooth. This guide walks you through what happens during a root canal, what you will feel, how long a root canal takes and what to expect afterwards.

Before treatment: why the tooth needs a root canal

The pulp is the soft tissue in the centre of the tooth, with nerves and blood vessels running down the root canals. Deep decay, a crack, a leaking filling or an injury can let bacteria reach it, and once the pulp is badly inflamed or infected it cannot heal by itself. Root canal treatment is then the way to save the tooth. If you are not sure whether your symptoms point to a root canal, read do I need a root canal? How dentists decide and our toothache page.

The root canal procedure step by step

Illustration: the main stages of root canal treatment on a lower back tooth. Simplified side view; the number of visits varies. Not a patient photograph.

Step 1: Examination and X-rays

Your dentist asks about your symptoms, examines the tooth and gum, and may test how the tooth responds to cold or tapping. X-rays show the shape and number of roots, any infection at the root tips and the bone around them. Sometimes a 3D CBCT scan is used for a complex tooth. Your dentist then explains the treatment, the likely number of visits and the final restoration the tooth will need.

Step 2: Root canal under local anaesthesia

The tooth and the gum around it are numbed with local anaesthetic, in the same way as for a filling. Once the tooth is numb, you should feel pressure and vibration, but not sharp pain. If you feel any pain during treatment, raise your hand; more anaesthetic can be given. A very inflamed tooth can sometimes take longer to numb fully.

Step 3: Isolating the tooth with a rubber dam

A thin sheet called a rubber dam (or dental dam) is placed around the tooth and held with a small clip. It keeps the tooth clean and dry, stops saliva and bacteria getting into the canals, and prevents small instruments and rinsing solutions from going into your mouth. Using a rubber dam is a standard part of root canal treatment (European Society of Endodontology, 2006; Ahmad, 2009). You can breathe normally through your nose and mouth.

Step 4: Opening the tooth and removing the pulp

The dentist makes a small opening in the top of the tooth (or the back of a front tooth) to reach the pulp chamber. Any decay is removed, and the inflamed or infected pulp is taken out of the chamber and the root canals.

Step 5: Measuring, cleaning and shaping the canals

The length of each canal is measured, usually with an electronic measuring device and X-rays, so the canals can be cleaned right to the tip of the root. Fine files are then used to clean and shape the canals, while disinfecting solutions are rinsed through them to wash out bacteria and debris. Some clinics also use a laser to help disinfect the canals; read root canal treatment with laser disinfection.

Step 6: Medicine and a temporary filling between visits

If the treatment is spread over more than one visit, a medicine is placed inside the canals to keep killing bacteria, and the tooth is sealed with a temporary filling. Try to chew on the other side, and call the clinic if the temporary filling comes out.

Step 7: Filling and sealing the root canals

When the canals are clean and the tooth is settled, they are filled with a rubber-like material called gutta-percha and a sealer, which seal the canals from the root tip to the top. An X-ray is usually taken to check the filling. The top of the tooth is then closed with a filling.

Step 8: Restoring the tooth with a crown

A root-filled tooth, especially a back tooth, is weaker and can break under biting forces. Most back teeth need a crown to protect them; some front teeth can be restored with a filling. This is a separate stage, often at later visits. Read crown after root canal treatment and see our crowns and bridges page.

How long does a root canal take?

How long a root canal takes depends mainly on the tooth. A front tooth usually has one canal, while a molar can have three or four, often curved or narrow, so back teeth take longer. Treatment also takes longer if there is a lot of infection, the tooth has been treated before or the canals are hard to find.

Some teeth can be treated in a single visit, while others are better treated over two or more. Reviews comparing single-visit and multiple-visit treatment have found no clear difference in healing between the two (Manfredi and colleagues, 2016). Your dentist will tell you how long each appointment is likely to take, how many visits your tooth needs and when the crown will be made.

Illustration: what to expect before, during and after a root canal appointment. Simplified checklist. Not a patient photograph.

What you will feel during and after the procedure

During treatment, most people feel pressure and vibration rather than pain, and many say it feels similar to having a filling. Your jaw may feel tired from keeping your mouth open, so you can ask for short breaks.

After the anaesthetic wears off, it is common for the tooth to feel tender or sore on biting for a few days. This usually settles with the pain relief your dentist recommends. Contact the clinic if you have swelling, severe pain that is getting worse, a reaction to medicine, or if the temporary filling comes out. For more on pain, read is root canal treatment painful? Myths vs facts.

Aftercare between and after visits

• Do not eat until the numbness has gone, so you do not bite your lip, cheek or tongue
• Chew on the other side until the tooth is fully restored, and avoid hard or sticky foods
• Keep brushing and cleaning between your teeth as normal, gently around the treated tooth
• Take any medicines exactly as advised
• Go back for every planned visit and for the crown, because a tooth left with a temporary filling can leak or break

ADC patients can follow the aftercare guides for each stage: instructions after root canal treatment stage I, stage II and stage III.

Root canal treatment at ADC, Chandigarh

At ADC – Centre for Restorative and Implant Dentistry, root canal treatment is usually carried out by Dr. Rosy Dhawan, MDS (Conservative Dentistry and Endodontics), and crowns are carried out by Dr. Mohit Dhawan, MDS (Prosthodontics). Because both are done in the same clinic, the root canal treatment and the crown can be planned together. Learn more on our root canal treatment page, in root canal treatment in Chandigarh: a patient's guide and in how root canal treatment saves your natural teeth. The clinic is in Sector 21, Chandigarh, within easy reach of Mohali, Panchkula and Zirakpur.

Frequently asked questions

Is a root canal done under local anaesthesia?
Yes. The tooth and the area around it are numbed with local anaesthetic, so you should feel pressure but not sharp pain. Tell your dentist if you feel any discomfort, so more anaesthetic can be given.

How many visits does a root canal take?
Some teeth are treated in one visit, others over two or more, depending on the tooth, the number of canals and how much infection there is. The crown is usually made at further visits.

Can I drive or go to work after a root canal?
Most people can, once the appointment is over, because local anaesthetic does not make you drowsy. You may prefer to rest if the appointment was long.

Can I eat after a root canal?
Wait until the numbness has worn off. Then eat soft foods and chew on the other side until the tooth has its final filling or crown.

What if the tooth hurts again later?
Mild tenderness for a few days is normal. If pain or swelling comes back weeks or months later, see your dentist; the tooth can often be treated again. Read root canal retreatment and how long does a root canal last?

Book a consultation in Chandigarh

This article is general information, not advice for any individual. Please speak with your dentist about your own situation. If you have toothache or have been told you need a root canal, you are welcome to book a consultation with Dr. Rosy Dhawan or Dr. Mohit Dhawan at ADC – Centre for Restorative and Implant Dentistry:

• Online booking: ADC Zoho Bookings
• Phone: +91-708-780-0016
• Email: help@theadc.dental
• Clinic: ADC- Centre for Restorative and Implant Dentistry, 1197, Sector 21B, Sector 21, Chandigarh, 160022, India

Mon–Fri 10:00 AM–6:30 PM; Sat 10:00 AM–5:00 PM; Sunday closed. You can also request a consultation online.

Reviewed by Dr. Mohit Dhawan, MDS (Prosthodontics, Crown & Bridge and Implantology).

References

1. European Society of Endodontology. Quality guidelines for endodontic treatment: consensus report of the European Society of Endodontology. Int Endod J. 2006 — PubMed 17180780
2. Ahmad IA. Rubber dam usage for endodontic treatment: a review. Int Endod J. 2009 — PubMed 19825034
3. Manfredi M, Figini L, Gagliani M, Lodi G. Single versus multiple visits for endodontic treatment of permanent teeth. Cochrane Database Syst Rev. 2016 — PubMed 27905673
4. NHS. Root canal treatment — nhs.uk
5. Cleveland Clinic. Root canal — clevelandclinic.org