Failure and retreatment
Persistent disease requires reassessment of diagnosis, missed anatomy, leakage, fracture and restorability. Compare retreatment, surgery, monitoring and extraction.
Understand
Persistent or recurrent apical disease may arise from missed canals, leakage, extraradicular pathology, root fracture or a wrong original diagnosis. Retreatment is not always the best option.
Assess
Compare old and new imaging, restoration integrity, periodontal probing and symptom pattern. Check access to the likely cause and the tooth's remaining prognosis.
Apply
Discuss orthograde retreatment, apical surgery, monitoring or extraction with likely benefit and burden. Refer complex anatomy or uncertain diagnosis, and use histology where surgery reveals unexpected tissue.
Key distinctions
Before retreatment, assess whether the tooth can be predictably restored afterward. Post removal, instrument retrieval or missed canal location may introduce new risks. Surgery may address a persistent apical lesion when orthograde access is impractical, but fracture and non-endodontic pain must be considered. Shared decision-making should include prognosis, treatment burden and an extraction option.
Think through a case
A retreated tooth has a narrow isolated periodontal pocket and persistent pain. A vertical root fracture may make further endodontics futile.
The distinction to remember
Do not choose retreatment from the radiolucency alone. Reassess restorability and non-endodontic explanations before another procedure.
Test your recall
What must be excluded before retreating a repeatedly symptomatic tooth?
Show answer
A vertical root fracture and a non-endodontic source of pain.