Symptoms & diagnosis
Treatment for infection around the root of a tooth
Infection inside the tooth can extend into the tissues around the tip of the root. For some patients this causes pain or swelling. In others, it may only become apparent on an X-ray.
How does a root canal infection develop?
When the pulp inside a tooth dies — following deep decay, a crack, trauma or a leaking restoration — bacteria colonise the root canal system. From there, infection can spread through the tip of the root into the surrounding bone, where the body's response produces the changes seen on a radiograph and, at times, an abscess.
Possible signs
- pain on biting or when the tooth is tapped;
- swelling of the gum or face;
- tenderness in the gum next to the tooth;
- a small draining spot on the gum that comes and goes;
- a dark area around the root tip on an X-ray, sometimes with no symptoms at all.
How treatment is decided
Treatment depends on whether the tooth has been treated before, whether it is cracked, whether it can be restored, and what is causing the infection. Possible treatment may include primary root canal treatment, root canal retreatment, or in selected cases endodontic surgery.
Antibiotics alone do not resolve an infection inside a tooth, because the source — the infected canal system — has no blood supply for the medication to reach. They may be prescribed in specific circumstances, such as spreading swelling, but the definitive treatment is removal of the source.
Benefits
- treatment directed at the source of infection;
- assessment of whether the tooth can be preserved;
- a plan based on the underlying cause rather than symptoms alone.
Important: rapidly increasing facial swelling, difficulty swallowing or breathing, or feeling generally unwell with a fever requires urgent medical assessment — contact NHS 111 or emergency services.