What Happens During Root Canal Treatment?

During root canal treatment, inflamed or dead tissue inside the tooth is removed. The root canals are prepared, disinfected and filled as tightly as possible. Afterwards, the tooth requires a durable definitive seal; depending on how much tooth structure has been lost, a partial crown or crown may also be appropriate. The number of appointments and prognosis depend on the individual findings.

Symptoms, sensitivity tests, tenderness to percussion, tooth mobility, gum findings and radiographic diagnostics help assess whether the dental pulp is inflamed or necrotic and whether changes are present around the root tip.

Before treatment begins, it is also assessed whether the tooth is fundamentally restorable. Deep fractures, very limited remaining tooth structure, uncontrolled inflammation or other risks can limit the prognosis and make alternatives necessary.

Treatment is generally carried out under local anaesthesia. The tooth is isolated from saliva and bacteria in the mouth. An access opening is then created so that the root canals can be located and treated.

With severely inflamed tissue, achieving effective anaesthesia can be more challenging. Symptoms and pre-existing conditions should therefore be discussed openly before treatment.

The working length of the canals is determined electronically and, where necessary, radiographically. Fine instruments enlarge and shape the canal system. Irrigating solutions help reduce tissue remnants and microorganisms.

Root canals can be curved, very narrow, calcified or anatomically branched. The natural canal system therefore cannot be simplified into a straight tube; treatment aims for the most thorough cleaning possible while preserving tooth structure.

Some treatments can be completed in one session. With pronounced infection, complex anatomy, persistent symptoms or organisational reasons, a medicated dressing with temporary sealing and an additional appointment may be appropriate.

A temporarily restored tooth should be loaded cautiously until definitive treatment is completed. If the temporary seal is lost or symptoms increase, prompt review is required.

Once the canals have been adequately prepared and the clinical conditions are appropriate, they are filled as tightly as possible. The access opening is then sealed against bacterial penetration.

Root-canal-treated teeth may already be weakened by caries, previous fillings and the access cavity required for treatment. Whether a direct filling, core build-up, partial crown or full crown is needed depends on the remaining tooth structure and functional loading.

Temporary tenderness to pressure or biting can occur after treatment. Follow-up examinations assess symptoms, function and — where medically indicated — radiographic changes over time.

More severe or increasing pain, swelling, fever, difficulty swallowing, loss of a temporary filling or fracture of the tooth require prompt dental assessment. In the event of breathing difficulty or rapidly increasing swelling, immediate medical help is required.

Root canal treatment can help preserve a restorable tooth and maintain its function over the long term, but it does not provide a guarantee of success. Possible difficulties include canals that cannot be located, instrument fracture, perforation, persistent or recurrent infection and tooth fracture.

Depending on the findings, options such as repeat root canal treatment, apical surgery or extraction followed by replacement of the missing tooth may be discussed. The decision takes into account tooth preservation, prognosis, treatment effort, risks and personal priorities.

Whether the tooth can be preserved and which treatment sequence is appropriate can only be determined after examination.