Root Canal Treatment.

What is root canal treatment?

Inside every tooth is a space containing nerve and blood vessels, the pulp. If bacteria reach it, through deep decay, a crack, a leaking filling or trauma, the pulp becomes irreversibly inflamed or dies, and infection spreads out through the root tip into the surrounding bone. Root canal treatment removes the contents of that space, disinfects and shapes the canals, and seals them so bacteria cannot recolonise.

Why has this been recommended?

Root treatment has been recommended because the pulp of this tooth cannot recover. Left alone, the likely outcome is worsening pain, an abscess, and eventual loss of the tooth. The alternative to root treatment is extraction, and I will always set out both, including what replacing the tooth would involve, so the decision is yours with the facts in front of you.

What to expect during treatment

The tooth is numbed thoroughly and isolated with a rubber dam, a small sheet that keeps the tooth dry and clean and stops anything reaching your throat. Access is made through the biting surface, the canals are located, and their length is measured electronically and confirmed radiographically.

The canals are then cleaned with fine instruments and disinfecting solutions. This is the part that determines success, and it is not something to hurry. Depending on the tooth, treatment is completed in one or two visits; between visits a medicated dressing and a temporary filling are placed. Once the canals are clean and dry, they are filled with a rubber-like material and sealer, and the access cavity is restored.

Most patients are surprised that the appointment itself is unremarkable. The pain people associate with root treatment is nearly always the pain that brought them in, not the procedure.

Risks and possible complications

Root treatment succeeds in the large majority of cases but not all. Canals can be curved, narrow, calcified or additional to the expected anatomy, and occasionally cannot be fully negotiated. Instruments can separate within a canal. Perforation of the root wall is uncommon but possible. Persistent infection sometimes requires re-treatment, surgery at the root tip, or eventually extraction.

Soreness for a few days afterwards is normal, and a minority experience a short-lived flare-up. A root-treated tooth is more brittle than a vital one and is prone to fracture, which is why back teeth are usually crowned afterwards. Front teeth sometimes darken over time and can be internally whitened.

Benefits and expected outcomes

The benefit is keeping your own tooth. Nothing we can make performs quite as well as a natural root in healthy bone, and retaining it preserves the bone and the neighbouring teeth. Success rates for well-executed root treatment are high, commonly quoted above 85 to 90 per cent at ten years for teeth that are then properly restored.

Aftercare and home care

Avoid chewing on the tooth until the permanent restoration is placed, particularly if a temporary filling is in. Take ordinary painkillers for the first day or two if needed.

Have the definitive restoration, usually a crown for a back tooth, completed promptly. A root-treated tooth left in a temporary filling will leak, reinfect and fracture, and that is the commonest reason these treatments fail. Then simply clean and review it as you would any other tooth; radiographs at intervals confirm the bone at the root tip is healing.

This page is written by Dr Steve Conteh, BDS (Hons) MSc, GDC 251055, and is general information rather than advice for your particular mouth. Your own plan, costs and risks are set out in writing before any treatment begins. Last reviewed August 2026.

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