In vitro comparative study of conventional radiography and Root ZX apex locator in determining root canal working length.

Success in endodontic treatment depends on various factors. One of the most important is appropriate preparation of the root canal system, in addition to keeping the periapical region intact as much as possible. This is achieved by determining the penetration depth of the instruments into the canal or the "working" length. Several methods are introduced for working-length determination. The most popular techniques are radiography and electronic apex locators. One type of apex locator is the Root ZX. The purpose of this study was to compare the accuracy of the Root ZX in vitro with conventional radiography.