Abstract
Prior to root canal treatment at least one undistorted
radiograph is required to assess canal morphology.
The apical extent of instrumentation and the final root
filling have a role in treatment success, and are
primarily determined radiographically. Electronic apex
locators reduce the number of radiographs required
and assist where radiographic methods create difficulty.
They may also indicate cases where the apical
foramen is some distance from the radiographic apex
Other roles include the detection of root canal
perforation. A review of the literature focussed first
on the subject of electronic apex location. A second
review used the names of apex location devices. From
the combined searches, 113 pertinent articles in
English were found. This paper reviews the development,
action, use and types of electronic apex
locators.