Wet or dry canals
What conditions does the apex locator need to work in? Some apex locators require dry or wet environments for proper functioning while others work in both. This factor will affect how you prepare the canal prior to inserting the file.
Accuracy
Your apex locator should be highly accurate in sensing the real-time location of the file. This is the instrument’s main function and it should be able to deliver on it.
Calibration
Some apex locators require you to calibrate them before you start using them while others calibrate automatically. Automatic calibration is more convenient and allows you to get a faster read.
Display
The display should be clear and easily interpreted so that you can quickly read it and know how close the apex locator is to the apex foramen. A compact apex locator is also preferable so that you don’t have to sacrifice valuable space for other tools.
Price
Cost is always an important factor to consider. Your apex foramen should fit within your budget while still delivering accurate readings.