This document classifies endodontic mishaps and errors into four main categories: access related, instrumentation related, obturation related, and miscellaneous. Access related errors include treating the wrong tooth, missed canals, damage to existing restorations, access cavity perforations, and crown fractures. Instrumentation related errors consist of ledge formation, cervical and midroot canal perforations, apical perforations, separated instruments, canal blockage, loss of working length, over or under instrumentation, and blockage of the canal system. Obturation related errors are over- or under-extended root canal fillings and nerve paresthesia. Miscellaneous errors include post space perforation, irrigant related issues, tissue

1. ENDODONTIC MISHAPS

2. Classification
By Ingle
Access related
• Treating the wrong tooth
• Missed canals
• Damage to existing
restoration
• Access cavity
perforations
• Crown fractures
Instrumentation
related
•Ledge formation
•Cervical canal
perforations
•Midroot
perforations
•Apical perforations
•Separated
instruments and
foreign objects
•Canal blockage

3. Obturation related
• Over- or under extended root canal fillings
• Nerve paresthesia
• Vertical root fractures
Miscellaneous
• Post space perforation
• Irrigant related
• Tissue emphysema
• Instrument aspiration and ingestion

4. ACCESS RELATED ERRORS

5. Treating the wrong tooth
Missed canals
Access cavity perforations
Damage to existing restoration
Crown fractures

6. INSTRUMENTATION RELATED

7. Loss of working length
Blockage of the canal system
Over instrumentation
Over preparation
Under preparation

10. Recapitulation
The reintroduction and reapplication of
instruments previously used, throughout the
cleaning and shaping process to create a well-
designed, smooth, unclogged, evenly tapered,
unstepped root canal preparation.

11. Ledging
Ledge is an artificially created
irregularity on the surface of the root
canal wall that prevents the
placement of instruments to the apex
of an otherwise patent canal.

12. Zipping
Or Elliptication, refers to
transposition or transportation of
the apical portion of the canal.

13. Transportation is defined as “removal of canal wall
structure on the outside curve in the apical half of the
canal due to the tendency of files to restore themselves
to their original linear shape during canal
preparation.”

14. ENDODONTIC PERFORATIONS
• An endodontic perforation may be defined as
"an artificial opening in a tooth or its root,
created by boring, piercing, cutting, or
pathologic Resorption, which results, in a
communication between the pulp canal and the
periodontal tissues".

16. The more apical the perforation, the
more favorable the prognosis