Trust your apex locator Radiographs are a great guide to where the apical foramen is but if you are experienced with the apex locator it's more likely to be correct! The master cone radiograph of tooth 36 (which is the length the apex locator confirmed) looks short! But when you check the post op radiograph is spot on! Radiographs are a helpful tool but tell you very little about where the apical construction is.

Should I trust my apex locator reading ???