Apical preparation size in endodontics: a review

Bacteria and their products are the major etiologic factors in endodontic treatment. Therefore, reduction of bacterial contamination is the main aim of endodontic treatment. The goal will be reached with an appropriate chemo-mechanical preparation along with preservation of as much of tooth structure as possible. The apical limit of root canal instrumentation and obturation is one of the major controversial issues in root canal therapy. So this article provides an overview of importance of anatomy of apex and current concepts regarding the apical preparation size for individual tooth.