Apex Locator

How to Use your Apex Locator (updated Dec 2022)


We will be measuring our working length @ 2 very specific times during treatment. You can measure more if you want, but these are the basic times to increase efficiency. You can spend all day measuring working length and accomplish nothing. Let's not do that.

Critical Working Length Measurements:

Initial working length (IWL) before using the Wave One Gold Primary

Final Working Length (FWL) after using the W1G Primary File.

There are 2 basic techniques that can be used with an apex locator.

  1. Insurance Policy Technique.
  • If you want to be sure you're at length, kiss the PDL with the file and go to 3 red bars and slowly unscrew to 1 red bar
  • Subtract 1mm or .5mm from this length

Note: I'll use this technique about 98% of the time.

2. Ricucci Technique (I'm just calling it that).

  • Take your file to the top of the green area and measure from there.
  • I"ll use this technique if I can't get to 1 red bar (ie - dilaceration, etc)
  • I'll try not to use this in necrotic teeth (no science behind that decision, just experience)

PDL Simulator Fabrication

Objective: Review how to make your PDL Simulator

Things you'll need:

  1. Alginate
  2. Plastic Cup
  3. "Watery Alginate Mix"
  4. Scissors
  5. Patience

Apex Locator Tips

Complete and Continue