What is root canal treatment?
Every tooth has a soft core called the pulp, which contains nerves and blood vessels. When deep decay, a crack or repeated dental work lets bacteria reach the pulp, it becomes inflamed or infected. Left alone, the infection can spread to the bone at the tip of the root and form an abscess.
Root canal treatment (endodontic therapy) removes the damaged pulp, shapes and disinfects the narrow canals inside the root, and fills them with a biocompatible material. The tooth then keeps its roots, its place in the jaw and its natural bite, which is why our dental team treats it as the first option for saving a natural tooth before considering extraction.
Signs you may need a root canal
- Lingering pain after hot or cold drinks, rather than a brief twinge
- Throbbing toothache that wakes you at night
- Pain when biting or tapping on one tooth
- Swelling or a small pimple-like bump on the gum
- A tooth that has darkened after an injury
Some infected teeth cause no pain at all and are found only on an X-ray during a routine dental check-up. Short, sharp sensitivity is often a different problem; our page on treating sensitive teeth explains the difference.
Who is root canal treatment suited for?
It suits patients whose tooth has a healthy enough root, enough remaining structure to support a crown, and gums and bone in reasonable condition. If a tooth is split below the gum line or has lost most of its supporting bone, keeping it may not be realistic. In that case Dr. Ryu Si-ho and our dental team will explain why, and discuss options such as replacing the tooth with a single implant. We always tell you whether treatment must be done now or whether it can safely wait.
The root canal process at E&D Dental, step by step
- Diagnosis. We examine the tooth, test its response and take images. Where root anatomy is complex, we use low-dose 3D CBCT imaging to see extra canals, curves and infection around the root tip.
- Anesthesia. Our 3-step painless anesthesia system starts with a topical gel or gargle, then cold numbing of the injection point with Endo-Frost, then a slow, steady dose from a computer-controlled anesthesia device.
- Access and cleaning. A small opening is made in the crown. The infected pulp is removed and each canal is shaped with fine instruments.
- Ultrasonic disinfection. The canals are irrigated with disinfecting solution activated by the UC ONE ultrasonic system, which helps the solution reach side branches that files cannot. Learn more about ultrasonic root canal cleaning.
- Filling and sealing. The clean canals are filled and sealed. If infection is significant, a medicated dressing may be placed first and the tooth sealed at a later visit.
- Protective restoration. Back teeth usually need a crown afterwards, because a treated tooth is more brittle. See our page on dental crowns.
Most root canals take two to three visits, depending on the number of canals and the amount of infection.
Recovery and aftercare
Mild tenderness when chewing is common for a few days and usually settles with over-the-counter pain relief. Until the final crown is fitted:
- Chew on the opposite side and avoid very hard or sticky food
- Keep brushing and flossing normally around the tooth
- Contact us if swelling increases, pain worsens after three days, or the temporary filling falls out
Once restored, the tooth should be cared for like any other, with regular check-ups and professional cleaning.
Risks and limitations
Root canal treatment is a well-established way to keep a tooth, but no dental procedure can promise permanent results. Very curved or calcified canals, hidden cracks or later new decay can lead to reinfection. In those cases root canal retreatment or root-end surgery (apicoectomy) may still save the tooth. Occasionally, a temporary flare-up of pain occurs between visits; we will see you promptly if it does.
Why patients in Sanbon and Gunpo choose E&D Dental for root canals
- Tooth-saving first: we explain why treatment is recommended and when keeping your own tooth is realistic.
- Precise diagnosis: 3D CBCT imaging and the Q-ray intraoral camera help us see cracks and decay clearly.
- Thorough disinfection: UC ONE ultrasonic irrigation is part of our endodontic routine.
- Comfort-focused anesthesia: a three-stage approach designed to reduce injection discomfort.
- Safe care for medically complex patients: vital-sign monitoring is available for elderly patients and those with chronic conditions.
- Convenient location: about a 5-minute walk from Sanbon Station on Line 4, with evening hours on Mondays and Thursdays.
If you are an international resident, we can help arrange English communication; please ask when booking. To arrange an assessment, contact our Sanbon clinic or read what to expect on your first visit.