The Root Canal Procedure Step by Step

Many patients feel anxious about root canal treatment simply because they don't know what's involved. I find that understanding the process takes away much of that anxiety. Here's exactly what happens when you come to my Carlow practice for root canal treatment.

Step 1: Diagnostic X-Ray

Before anything else, I'll take a detailed X-ray of the affected tooth and surrounding bone. This shows me the shape of the root canals, the extent of the infection, and whether there's any bone involvement. In some cases, I may take several X-rays from different angles to get a complete picture.

Step 2: Local Anaesthesia

I'll administer a local anaesthetic to numb the tooth and surrounding area thoroughly. This is the same type of injection used for fillings, and once it takes effect, you should feel no pain during the procedure — only some pressure and vibration. If you're particularly anxious, we can discuss additional options to help you feel more comfortable.

It's worth noting that even if your tooth has been causing severe pain beforehand, the anaesthetic will block that pain completely during treatment. In fact, many patients feel relief even before the procedure is finished.

Step 3: Rubber Dam Isolation

I'll place a thin rubber sheet (called a rubber dam) around the tooth. This isolates the tooth from the rest of your mouth, keeping it dry and free from saliva during the procedure. It also prevents any small instruments or cleaning solutions from entering your throat. Most patients find the rubber dam quite comfortable once it's in place, and it means you can relax and breathe normally throughout.

Step 4: Access Opening in the Crown

Using a small dental drill, I create an opening in the top (crown) of the tooth to access the pulp chamber inside. For a back tooth, this opening is made on the biting surface; for a front tooth, it's made on the back surface. The opening is only as large as necessary — I aim to preserve as much of your natural tooth structure as possible.

Step 5: Remove the Infected Pulp

Using specially designed, very fine instruments called endodontic files, I carefully remove the infected or inflamed pulp tissue from the pulp chamber and the root canals. This is the core of the procedure — once the infected tissue is removed, the source of your pain and infection is gone.

Step 6: Clean and Shape the Canals

With the pulp removed, I use a series of progressively larger files to clean and shape the inside of each canal. This step is crucial because it removes any remaining bacteria and debris, and creates a smooth, tapered shape that can be sealed effectively. The number of canals varies depending on the tooth — front teeth typically have one, while back molars may have three or four.

Step 7: Irrigate with Antiseptic Solution

Throughout the cleaning process, I flush the canals repeatedly with an antiseptic solution (usually sodium hypochlorite). This kills any remaining bacteria in areas that the instruments can't physically reach and washes away debris. The canals are then dried with small absorbent paper points.

Step 8: Fill the Canals with Gutta-Percha

Once the canals are clean, dry, and shaped, I fill them with a biocompatible rubber-like material called gutta-percha. This material is heated and compressed into the canals to create a tight seal, preventing bacteria from re-entering. A sealer cement is used alongside the gutta-percha to ensure a complete seal.

Step 9: Seal with a Temporary Filling

The access opening in the crown of the tooth is sealed with a temporary filling material. This protects the tooth between appointments while we arrange for your permanent crown. In some straightforward cases, I may be able to place a permanent filling at this stage.

Step 10: Follow-Up for Permanent Crown

Within 2–4 weeks, you'll return for the final stage — fitting a permanent dental crown over the treated tooth. This is essential. A root-canal-treated tooth is more brittle than a living tooth because it no longer has a blood supply. A crown provides the strength and protection needed to ensure the tooth lasts for many years. I'll discuss crown options with you, including the material and appearance, during your treatment planning.

Pain Management

During the Procedure

The procedure itself should be painless thanks to the local anaesthetic. You'll feel pressure as I work inside the tooth, and you'll hear the drill and other instruments, but there should be no sharp pain. If at any point you feel discomfort, raise your hand and I'll stop immediately to administer more anaesthetic.

After the Procedure

Once the anaesthetic wears off (usually 2–4 hours later), some tenderness around the treated tooth is normal. This is your body's natural response to the treatment and typically lasts a few days. Over-the-counter painkillers such as ibuprofen or paracetamol are usually sufficient. I'll give you specific advice on pain management before you leave.

Most patients return to normal activities the next day. The discomfort after a root canal is generally far less than the toothache that brought you in.

How Long Does It Take?

A typical root canal appointment lasts between 1 and 2 hours, depending on:

Which tooth is being treated — front teeth with a single canal are quicker than molars with three or four canals
The complexity of the canal anatomy — some teeth have curved or narrow canals that require more time
The severity of the infection — heavily infected teeth may require two separate appointments, with a medicament placed inside the canals between visits to help eliminate the infection

I'll give you a clear idea of the expected treatment time and number of appointments after my initial assessment and X-rays. My aim is always to complete the treatment as efficiently as possible while being thorough — there's no benefit to rushing.

For information on looking after yourself after the procedure, see my root canal aftercare guide.

What to Expect During Root Canal Treatment