endodontic complications

Question 1

endo complication definition

Answer 1

“a secondary disease or condition aggravating an already existing one”

Question 2

types of complications in endo

Answer 2

Complications with access
Complications of instrumentation
Post op complications

e.g. roof of pulp chamber not removed

Question 3

endo perforation - how to prevent and avoid

Answer 3

Plan from pre-op
Inspect external surfaces
Think where are you in relation to the ACJ
Think centrality and concentricity
Consider other points of reference

Knowledge of expected anatomy
Looking at pictures/lecture notes
Looking at or in extracted teeth

Measuring pre-op radiograph to pulp chamber roof/floor
Dg 16 and rubber stopper as depth gauge
“Go for the pulp horns”
Practice

Question 4

preserve anatomy in endo

Answer 4

by using endo access bur

Question 5

complete removal of roof of pulp chamber

Answer 5

safe removal of roof of pulp chamber helps to gain access to all canals

provides a reservoir for irrigants during instrumentation

Question 6

complications of endo instrumentation

Answer 6

Blockage
Ledges
Apical damage (zipping / transportation /enlargement)
Perforation
Fractured instrument

Question 7

conventional hand filing endo prep complications

Answer 7

Mishaps (ledges, canal blockage, zipping of foramen)
Debris extrusion with filing motion
Time consuming
Less predictable shapes in curved canals with inexperienced operators

Question 8

endo blockage

Answer 8

caused by dentine debris getting packed into apical portion of the root

when tightly packed = hard as surrounding dentine
attempts to remove it can cause false canal being cut

Question 9

endo ledges

Answer 9

A ledge is internal transportation of the canal

Occurs when working short of length

Can be bypassed but difficult
Time consuming

!!!!!
If curved canals are instrumented as if
they were straight, ledging will occur and the apical few mms will remain
uninstrumented and infected

Question 10

apical zipping/transportation consequences

Answer 10

Occurs as a result of the tendency of the instrument to straighten inside a curved canal

Over-enlargement along the outer side of curvature
Under-preparation of the inner aspect at the apical end point
The main axis of the canal is transported
Results in a teardrop or hour-glass shape

Question 11

apical zipping/transportation avoidance

Answer 11

Always pre-curve the initial small sized hand instruments
Do not skip instruments in the sequence
Never rotate the instruments in curved canals

Question 12

apical transportation and GP’s

Answer 12

Transportation of the apical foramen fails to provide resistance for packing of gutta-percha

Cases tend to be overextended and poorly filled

In minor cases the canal can be reshaped to a new level just above the foramen

In more severe cases bleeding is a problem and attempting to reshape can result in weakening or perforating the root

Question 13

diagnosis of root perforation

Answer 13

persistent bleeding into canal
multiple radiographs
electronic apex locators
dental operating microscope

Question 14

prognosis of perforation depends on

Answer 14

Location
Time elapsed
Size
Periodontal irritation
Material used for repair

Question 14

endo instrument separation

Answer 14

Torsional stress
Extensive instrument surface encounters excessive friction on canal walls
Instrument tip is larger than canal section to be shaped
Tip may lock, torque exceeds critical level

Flexural stress
Repeated cyclic metal fatigue
Cannot be influenced by clinician

Question 15

endo post op complications

Answer 15

Pain
Swelling
Need for pain control
Failure
Prosthetic replacement

Question 16

common endo pitfalls

Answer 16

Access:
Access too big/too small
Roof of pulp chamber not removed adequately
Perforation

Mechanical preparation:
Blockage
Separated file
Ledge

Obturation:
Too short/too long
Voids
Too much GP in pulp chamber
GP in other canals (loss of control)

General:
Read and follow instructions
OSCE/future exams

Question 17

if endo prep too short

Answer 17

Error in WL determination
Error in preparation
Blockage
Ledge formation
Incomplete preparation
Error in obturation

Question 18

how to avoid short endo prep

Answer 18

Good pre-op radiograph and EWL measurement
Use of Apex locator and WL radiograph

Care in selecting reference point and using it

Apical gauging/ensure MAF passive in canal
Try in of master cone

Question 19

how to avoid endo blockages

Answer 19

Don’t skip files
Don’t force files
Ensure file you are using is passive prior to moving to a bigger file
Recapitulate and patency file

Irrigate, irrigate, irrigate
Have reservoir of irrigant in pulp chamber whilst instrumenting

Question 20

how to avoid fractured files

Answer 20

Know limits of instruments

Using a recognised technique!

Pay attention to degrees of rotation

Stay focussed

Lubricate canal

Know settings of rotary – for another time

Question 21

deviations in canal anatomy

Answer 21

Ledges
Apical zipping
Over-instrumentation

Repeated placement to a given length with extended working

Question 22

how to avoid loss of control during obturation of GP in other canals

Answer 22

Obturate one canal at a time

Use of super endo alpha to remove excess

Use of Buchannan plugger to condense

Control – Practice

Magnification!