Diagnosis and management planning for rootfilled teeth with persisting or new apical pathosis

Teeth may require further management following root canal treatment because of persisting or new apical pathosis. Management must be based on the diagnosis of the presenting condition and the history of the previous treatment, particularly in relation to when it was completed. Most root-filled teeth with periapical pathosis should be re-treated in the first instance via a conventional orthograde approach since most disease is related to an infected root canal system. However, this approach to treatment should only be followed if the tooth is suitable for further restoration and when the restoration has a good long-term prognosis. Assessment of whether a tooth is suitable for treatment may not be possible until after restorations, caries, and cracks have been removed so that the remaining tooth structure can be visualized and assessed. Periapical surgery should be reserved for teeth with persistent symptoms and/or apical radiolucency following root canal re-treatment and where the differential diagnosis suggests an ongoing periapical condition such as a true cyst, extra-radicular infection, or foreign body reaction which cannot be addressed via an orthograde approach. If a tooth has to be extracted, it can be replaced with one of several forms of prostheses; implant-supported prostheses are gaining popularity and have a proven track record, especially for single tooth replacements. The use of implants should be restricted to cases where teeth are already missing or where a tooth cannot be retained because it is not suitable for further restoration due to insufficient tooth structure.