endo 4th year Flashcards
what is failure?
presence of clinical S/S
enlargement of existing PR lesion
development of a new PR lesion
persistence of a PR radiolucent lesion associated with a tooth that had RCT at least 4 years prev
tx options for failure
monitor if asymptomatic
orthograde retx
PRS
extract +/- prosthesis
what must be mentioned if it is decided to monitor failure?
inform pt of possibility of a flare up
not ideal to monitor if tooth is a critical abutment in a definitive complex Rx
indications for non-surgical retx
intra-radicular infection
new complex restoration with technically poor RCT
loss of coronal seal
principles of retx
remove restorative assess restorability - check no fracture remove all root filling assess anatomy refine/modify prep complete tx as de novo case
removing insoluble resins
US
removing GP
handfiles
solvent (eucalyptus oil)
reciproc
removing soluble pastes
handfiles
solvent (eucalyptus oil)
reciproc
reciproc retx removing GP
remove GP from coronal 1/3 - US, GG, heat carrier
remove GP from mid 1/3 - R25 with stopper set at 2/3 of EWL - slow pecking motion
continue until GP removed from middle 1/3 of canal - use eucalyptus oil/chloroform if necessary
determine WL with small hand file
complete apical prep to CWL with R25. if necessary enlarge apical prep with R40/50 or K files
how do you use a solvent?
fill orifice and pulp chamber
why should you try to avoid solvents?
they lead to more GP and sealer remnants on RC walls, chamber and inside dentinal tubules
when is WW good?
with K files
passing small files through canals
balanced force technique
insert file and engage into dentine clockwise 1/4 turn
with continued pressure, 1/2 turn anticlockwise to strip dentine away
do 1-3 times before removing file
clean, check file, reintroduce, working your way to WL
safer for canal and file
reciproc file features
non-cutting tip
S shaped cross section
NiTi
reciproc R25
red
narrow canals
ISO25
reciproc R40
black
medium canals