Endodontic treatment part 2: root canal preparation and obturation

In part 1 of this series we described a patient with pulpal inflammation leading to a pulpitis (Emery, 2015). The microorganisms causing this will now have established themselves in the necrotic pulp space. This means that this dead tissue has no access to inflammatory healing mechanisms, as it no longer has a blood supply. The only treatment choices are extraction or root canal therapy (RCT). Also, as this necrotic tissue breaks down and the bacterial activity increases, chemical mediators called endotoxins permeate through the multiple root foramina and create an inflammatory reaction in the periodontal ligament, a condition known as periradicular periodontitis. This process causes tenderness, which immediately assists the patient and clinician in locating the ‘guilty’ tooth, hence clarifying the diagnosis. As a result of this continuing periradicular inflammation, the adjacent bone undergoes a reactive resorptive phase (where the bone breaks down and dissolves), which can produce a radiolucency that can be apparent on a well-directed radiograph.