Unusual anatomy of mandibular premolars.

Mandibular premolars usually have a single root and canal; however, during clinical and radiographic evaluation as part of endodontic treatment it must be noted that variations in anatomical configuration are not uncommon. These teeth may require special canal preparation and filling techniques. This article discusses the treatment recommendations for unusual anatomical configurations in two different mandibular premolars and reports the treatment carried out on these teeth.