Endodontic complications Flashcards
How to avoid perforation?
- plan from pre- op radiograph
- inspect external surfaces
- think where you are in relation to ACJ
- THINK CENTRALITY AND CONCENTRALITY
Why complete removal of roof of pulp chamber?
- gain access to all canals
- provides reservoir for irrigants during instrumentation
Complications of Instrumentation
- blockage
- ledges
- apical damage (zipping/ transportation/ enlargement)
- perforation
- fractured instrument
Blockage
- caused by dentine debris getting packed into apical portion of root
- when packed tightly it can be as hard as dentine
- attempts to remove it can result in a false canal being cut and possible perforation
Ledges
- terminal transportation of canal
- occurs when working length is short
- can be bypassed by difficult and time consuming
- if curved canals are instrumented as straight, ledging will occur and apical few mms will remain uninstrumented and infected
Apical zipping/ transportation
- result of tendency of instrument to straighten inside a curved canal
Consequences of apical zipping/ transportation
- over- enlargement along outer side of curvature
- under prep of inner aspect at apical end point
- main axis of canal is transported
- results in teardrop/ hourglass shape
How to avoid apical zipping/ transportation
- pre-curve initial small sized hand instruments
- do not skip instruments in any sequence
- never rotate instruments in curved canal
What happens if apical transportation happen?
- fails to provide resistance for packing of GP
- tends to be overextended and poorly filled
- in minor cases, canal can be reshaped to new level just above foramen
- in more severe cases, bleeding is a problem and might weaken/ perforate root
Diagnosis of root perforation
- persistent bleeding into canal
- multiple radiographs
- electronic apex locators
- microscope
Instrument separation
Torsional stress
- extensive instrument surface encounters excessive friction on canal walls
- instrument tip is larger than canal section
Flexural stress
- repeated cyclic metal fatigue
- curved canal
Post op complications
- pain
- swelling
- need for pain control
- failure
- prosthetic replacement
Common pitfalls
Access
- too big/ too small
- roof chamber not removed adequately
- perforation of floor of pulp chamber
Mechanical preparation
- blockage
- separated file
- ledge
Obturation
- too short/ too long
- voids
- too much GP in pulp chamber
- GP in other canals
Obturation length too short?
- error in WL
- error when prep; blockage, ledge formation, incomplete prep
- error in obturation
Avoid blockage
- dont skip files
- dont force files
- recapitulate and use patency file
- irrigate
- have reservoir of irrigant in pulp chamber while instrumenting
