Apex Locators

Apex locators such as Root ZX are instruments that allow us to measure root length with great precision. Because Radiographs are 2 dimensional images of 3 dimensional objects, estimating working length from radiographs is very imprecise. Unfortunately, for many years there was no alternative. However, with the new generation of apex locators on the market, there is no excuse not use them.

A 1999 study published in the International Journal of Endodontics showed Root ZX apex
locator to be 96.2 % accurate vs. 63 % for radiographs.