Mandibular premolar with three root canals--two case reports.

The presence of three root canals in the mandibular premolar may sometimes be recognized when there is persistent postoperative discomfort following root canal therapy. This paper presents two cases of root canal treatment of mandibular premolars with three root canals including one mandibular first premolar and one mandibular second premolar. The possibility that there is more than one root canal in lower premolar teeth must be considered in the radiographic and clinical examination during root canal treatment.