Wrong working length (no apex locator / poor WL confirmation)
What it is
Setting (and then preparing/obturating) the canal length too long or too short because WL was guessed, based only on a single radiograph, not confirmed, not re-checked, or because an electronic apex locator (EAL) wasn't used correctly.
Why it happens
• No EAL used (or relying on tactile sensation only) • Poor radiographic technique (angulation errors, distortion, missing the true apex) • No confirmation step: WL not verified with a file radiograph and/or not re-checked after coronal flaring • Anatomy factors: apical foramen not at the radiographic apex; curved canals; resorption; open apex • Clinical workflow errors: rubber stop movement, not locking the reference point, not maintaining patency, debris blocking apical region
The full clinical mistake entry includes
- How to avoid it — the prevention protocol
- The clinical tip experienced clinicians use
- The documented reference behind the mistake
More clinical mistakes
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