Root canal treatment of a mandibular second premolar with atypical canal pattern.

To present a unique case of mandibular second premolar with an atypical canal pattern. Thorough knowledge of root canal morphology, appropriate assessment of the pulp chamber floor, and critical interpretation of radiographs are a prerequisite for successful root canal treatment. Mandibular premolars frequently exhibit variable and complex root canal morphology and are one of the most difficult cases to treat endodontically. These teeth may require skillful and special root canal preparation and obturation techniques. This article reports an unusual case of a mandibular second premolar with atypical canal pattern that was successfully treated endodontically.