Root Canal Treatment: What It Is and How It Works
Root canal treatment, also called endodontic treatment, treats damage to the pulp tissue inside a tooth, which contains nerves and blood vessels. Infection, advanced decay or trauma can damage the pulp. The aim is to preserve the tooth rather than extract it . This guide explains when root canal treatment is considered, microscope-assisted treatment, retreatment options and common questions.
What Is Root Canal Treatment?
Root canal treatment is used when the pulp inside a tooth is damaged . Infected tissue is removed from the pulp chamber and root canals, which are then cleaned and filled with biocompatible materials. The goal is to retain the natural tooth and its function.
An appropriate restoration, such as a filling, onlay or crown, helps restore chewing function. Successful treatment can preserve a tooth without extraction.
Symptoms That May Require Assessment
These symptoms may indicate a need for root canal assessment, but diagnosis requires an examination:
- Spontaneous pain that may worsen at night or when chewing
- Lingering sensitivity to heat
- A small gum swelling or sinus tract that may drain an abscess
- A tooth becoming darker, particularly after trauma to a front tooth
- Sharp pain on biting or pressure
- Severe toothache that persists or repeatedly returns
- Changes around the root tip visible on an X-ray
Early assessment can improve the opportunity to preserve a tooth. Ignoring symptoms may allow infection to spread and increase the risk of tooth loss.
Endodontic Treatment Options
Three main approaches may be considered. The choice depends on examination, imaging and the individual case.
Root Canal Treatment
First-time treatment of the tooth's pulp and root canals. Hand or rotary instruments are used to shape the canals.
Sources and further reading
Sources consulted: 26 September 2026. These references provide general background; treatment decisions require an individual examination.
Root Canal Retreatment
Cleaning and filling the canal system again when previous treatment has not resolved the problem. The aim is to preserve the tooth where possible.
Apical Surgery
Surgical treatment of the root tip and placement of a root-end filling when conventional treatment cannot resolve a persistent problem.
Treatment Stages
Root canal treatment may take one or more appointments, depending on complexity.
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Diagnosis and clinical assessment
Symptoms, pulp sensibility tests, percussion tests and periapical X-rays help establish the diagnosis. CBCT may be used in complex cases.
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Local anaesthesia
Local anaesthesia is used to keep the patient comfortable. The aim is effective pain control throughout the procedure.
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Rubber dam isolation
A thin rubber dam isolates the tooth from the mouth, reducing saliva contamination and protecting the cleaned canal system.
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Creating access
An opening is made through the biting surface or back of the tooth to reach the pulp chamber.
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Shaping and cleaning the canals
Hand or rotary instruments shape the root canals. Irrigating solutions, such as sodium hypochlorite and EDTA, are used to clean the canal system.
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Filling the canals
The cleaned and shaped canals are filled with gutta-percha and an appropriate sealer.
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Restoring the crown of the tooth
A composite filling may be suitable where little tooth structure has been lost. An onlay or crown may be recommended for heavily damaged back teeth. A sound final restoration is important for long-term success.
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Follow-up
Healing is assessed at follow-up. The need for X-rays and their timing depend on symptoms and the tooth's initial condition.
Microscope-Assisted Root Canal Treatment
A dental operating microscope provides magnification and illumination to help visualise fine canal anatomy, locate canal openings and identify remaining materials during retreatment .
A microscope can be useful in situations such as:
- Complex canal anatomy, including extra canals, isthmuses and canal connections
- Calcified or narrow canals
- A separated instrument within a canal
- Retreatment of a previously treated tooth
- Repairing a perforation
After Root Canal Treatment
Mild tenderness on pressure can occur for a few days. Your dentist can advise on suitable pain relief. Contact your dentist if you experience:
- Severe or persistent pain
- Noticeable facial swelling
- A high temperature
- Tenderness that prevents you from biting on the tooth
Daily oral care and completion of the recommended restoration are important for long-term success.
Significant symptoms after treatment
If you develop severe persistent pain, noticeable facial swelling, a high temperature or tenderness that prevents biting, contact your dentist promptly. These symptoms may indicate a complication that needs assessment.
At a Glance
| Treatment type | Endodontic treatment |
|---|---|
| Anaesthesia | Local anaesthesia |
| Number of appointments | One or more, depending on the case |
| Isolation | Rubber dam |
| Canal filling material | Gutta-percha and sealer |
| Final restoration | Composite filling, onlay or crown |
Frequently Asked Questions
Is root canal treatment painful?
Local anaesthesia is used to control pain during treatment. Removing the diseased pulp addresses a source of dental pain. Some tenderness may remain for a few days afterwards.
How long can a root-treated tooth last?
A suitably treated and restored tooth may function for many years with regular care and reviews. A fixed lifespan cannot be guaranteed; outcomes depend on the tooth and ongoing oral care.
How many appointments does treatment take?
It depends on complexity. A front tooth with one root may be treated in one visit, while molars or retreatment cases may need several appointments.
Can the tooth be extracted instead?
Root canal treatment aims to preserve a suitable tooth. After extraction, monitoring the gap or replacing it with an implant, bridge or denture may be considered. The choice is individual.
Does every root-treated tooth need a crown?
A crown or onlay may be recommended for back teeth with substantial loss of structure. A composite filling may be sufficient for a front tooth with limited damage. Your dentist assesses the remaining sound tooth structure.
Are antibiotics needed after root canal treatment?
Antibiotics are not routinely required. A dentist may prescribe them for spreading infection, systemic symptoms or specific risk factors. They do not replace treatment of the tooth.
Can root-treated teeth change colour?
Internal discolouration can occur, particularly after trauma. Internal whitening or restorative options may be considered.
Can children have root canal treatment?
Primary teeth may require procedures such as pulpotomy or pulpectomy. Permanent teeth can also need endodontic treatment in childhood. Planning takes the child's age and dental development into account.
Information and examination appointments
Individual medical advice requires a clinical examination. You can use the contact page to request an appointment.