A forty-six-year-old women with non-contributory past medical history complained of pain on the upper right quadrant. The second premolar (15) tested negative electyric sensitivity testing and was slightly sensitive to percussion and palpation. Periodontal probing revealed an eoght millimeter deep mesial pocket. Radiographically it was possible to see a small radiolucent area around the root tip and a deep mesial pocket. A fractured instrument indicating earlier failed treatment was seen in the apical canal.