Why do root canals have a painful reputation?
Root canal treatment earned its reputation decades ago, when anesthesia and instruments were less refined. Another reason is timing: people often arrive for a root canal when a tooth is already severely inflamed or abscessed, and that pain becomes linked in memory to the treatment rather than the problem. Today, the procedure is a routine way to save a natural tooth, and its purpose is to remove the source of pain.
What is actually happening inside the tooth?
Inside every tooth is a soft core called the pulp, containing nerves and blood vessels, which runs down through narrow canals in the roots. Deep decay, a crack or repeated dental work can let bacteria reach the pulp. Once it is inflamed or infected, it cannot heal on its own. Signs can include lingering sensitivity to hot or cold, pain when biting, a dull ache, swelling in the gum or a small pimple-like bump near the tooth. Sometimes there are no symptoms at all, and the problem is found on an X-ray.
Root canal treatment removes the damaged pulp, cleans and disinfects the canals, and seals them so bacteria cannot return. The tooth stays in place and continues to function.
What happens during a root canal, step by step?
- Diagnosis. The dentist tests the tooth and takes X-rays. For complex roots or suspected cracks, 3D CBCT imaging can show the canal anatomy in detail.
- Anesthesia. The tooth and surrounding area are numbed. At Seoul E&D Dental Clinic this follows our 3-step painless anesthesia system: a topical gel or gargle anesthetic, cold numbing of the injection point, and a computer-controlled delivery device that releases anesthetic slowly and steadily.
- Isolation. A thin rubber sheet is usually placed around the tooth to keep it dry and clean.
- Access and cleaning. A small opening is made in the crown of the tooth. Fine instruments remove the pulp and shape the canals.
- Disinfection. The canals are rinsed with disinfecting solutions. We use ultrasonic root canal cleaning with the UC ONE system, which activates the irrigating solution so it can reach small branches that instruments alone may miss.
- Sealing. The canals are filled with a rubber-like material and sealed.
- Restoration. A temporary or permanent filling closes the access hole. Back teeth commonly need a crown afterwards to protect against fracture.
Treatment may be completed in one visit or spread over two or more, depending on infection and how many canals the tooth has.
What does it feel like during treatment?
Once the tooth is fully numb, most patients report feeling pressure and vibration rather than pain. A badly inflamed tooth can occasionally be harder to numb, which is a well-recognised phenomenon in dentistry. In that case, the dentist can add more anesthetic or use additional techniques before continuing. You can raise a hand at any time to pause.
Our team also explains each stage as we go, because knowing what is happening tends to reduce tension. If anxiety is a concern, our article on managing fear of the dentist may help.
How much does it hurt afterwards?
It is normal for the tooth to feel tender or slightly bruised for a few days, especially when biting. This happens because the tissues around the root were inflamed before treatment and need time to settle. Many patients manage with over-the-counter pain relief, taken as directed. Practical tips include:
- Avoid chewing hard food on the treated tooth until the final restoration is placed.
- Keep brushing and flossing normally.
- Contact the clinic if swelling increases, pain worsens after several days, or a temporary filling comes out.
Do antibiotics replace a root canal?
Antibiotics can help control spreading infection or swelling in some situations, but they cannot clean out the infected tissue inside the tooth, because the pulp has no blood supply left for the medicine to reach. Relying on antibiotics alone usually means the pain returns. The cause has to be removed mechanically, either with root canal treatment or by extracting the tooth.
Is a root canal more painful than an extraction?
Both procedures are done under local anesthesia, and discomfort afterwards is usually comparable. The main difference is long-term: an extraction leaves a gap that may later need an implant, bridge or denture, while a root canal keeps your own tooth. Dentists generally recommend saving a natural tooth when it has a reasonable outlook. If a tooth cannot be saved, tooth extraction followed by replacement is discussed openly.
What if a root-canal-treated tooth hurts again?
Most root canal treatments heal well, but a tooth can become reinfected years later, for example if a canal was missed or the crown leaked. Options then include root canal retreatment, where the old filling material is removed and the canals cleaned again, or an apicoectomy, a small surgical procedure at the root tip.
Can I avoid needing a root canal?
Often, yes. Most root canals are the result of decay that was not treated early. Regular check-ups, prompt cavity treatment, and attention to cracks or lingering sensitivity give you a good chance of keeping the pulp healthy. Our Q-ray intraoral camera can help reveal early decay and cracks that are not obvious to the eye.
Root canal treatment at E&D Dental in Sanbon
Our approach focuses on three things: thorough cleaning of the canals, careful anesthesia designed to minimize discomfort, and clear explanation of whether treatment is needed now or can be monitored. The clinic is located in Sanbon-dong, Gunpo, around a five-minute walk from Sanbon Station on Line 4, with evening hours on Mondays and Thursdays for patients who work during the day. If a tooth is bothering you, please contact us to arrange an assessment; for sudden severe pain, see our emergency dental care page.