OBTURATIO
N
Topics to be covered
1. Obturation
a. Definition
b. Objectives
c. Assessment
d. Apical extent of root filling -Overfilling, Underfilling
e. Instruments
2. Root Canal filling Materials
a. Ideal properties
b. Types – Pastes
Semisolids – GP with sealants (Classification of
techniques and brief discussion)
Solids
3. Gutta Percha Removal
1. a) What is Obturation..?
• Obturate – to close or
obstruct
• Final step in
endodontic treatment
- sealing of apical
foramen at CDJ & all
portals of entry to
periapical tissue with
an inert material.
c) Assessment before obturation
• Tooth properly isolated to eliminate risk of
canal contamination
• Compacting instruments must be prefitted
into canal
• Moisture free prior to obturation
• In multirooted teeth, all efforts must be
expended to ensure that all the canals have
been cleaned and shaped properly.
When to Obturate….?
• Adequate biomechanical preparation has been
completed & confirmed.
• Tooth is asymptomatic
• Canals are dry
• No sinus tract
• No foul odour
• Intact temporary filling
d) THE APICAL EXTENT OF ROOT FILLING
• It has significant influence on outcome
• Flush root fillings have higher success
rates than short or long root fillings
LONG
SHORT FLUSH
Extruded beyond
>2 mm short of 0 – 2 mm within the
Radiographic apex
the radiographic apex Radiographic apex
i. Overfilling and Overextension
• Overfilling- “total
obturation of root canal
space with excess material
extruding beyond the
apical foramen”
• Overextension- “extrusion
of filling material beyond
the apical foramen but
canals have not been
adequately filled and the
apex has not been sealed”
ii. Underfilling
• Underfill results when
both preparation and
obturation are short of
the desired working
length or when
obturation does not
extend to the prepared
length
Tooth seen here with an under-prepared
and under-filled root canal treatment..
2. Root Canal Filling
Materials
a) Ideal root canal filling material
1. Be easily introduced into root canal
2. Seal the canal laterally & apically.
3. Not shrink after being inserted.
4. Impervious to moisture.
5. Bacteriostatic, or at least not encourage bacterial
growth.
6. Be radiopaque.
7. Not stain tooth structure.
8. Not irritate periapical tissues
9. Be sterile, or atleast easy to sterilize
10. Be easily removed from root canal if necessary.
b) Types
• Pastes
Gutta Percha
• Semisolid
Resilon
• Solids
– Silver points
ii. Semi Solids - GP with sealants
1. Cold GP
a) Lateral compaction
b) Variations to lateral compaction
i. Reverse cone technique
ii. Rolled cone technique
c) Single cone method
2. Canal warmed GP
a) Vertical compaction
b) System B
c) Thermomechanical compaction
3. Thermoplasticized GP
a) Obtura II
b) Thermafil
• Gutta flow
1. Cold GP- a) Lateral
Compaction
b.Variations i) Reverse cone
technique
• Butt end of GP is inserted to achieve tug-
back
ii) Rolled-cone technique
• Tailor made roll used for
BlunderBuss canals.(canal
is wider at the apex than
cervical)
• Fusing multiple cones
together butt to tip
• Softened with heat
• Rolled & chilled
• If too large then can be
flash heated
2.Canal warmed GP - a) Vertical
compaction
• Schilder technique or
warm GP technique
• Lateral & accessory
canals
• Used with step back
prep
• Master cone selection
• Sealer application
• Cement master cone
• Coronal end of cone cut
off
• Heated plugger forced into
coronal 3rd- gets seared off
• Vertical condenser inserted,
vertical pressure applied to
force it apically
• Steps repeated until all
accessory canals and lumen
filled
• Remaining portion of canal
plugged with warm sections
of GP
b) System B – “continuous wave of
condensation” (Buchanan)
• Employs thermostatically controlled
heat source, softens GP in apical 4-5
mm with one application of heat
• Application of sealer
• Insertion of master cone and heat
application from pre-selected tip,
that delivers heat to apical 1/3rd
• Heat turned off before reaching
predetermined length and forces
last few mm in cooled state
• Cold plugger vertically compacts the
remaining cooling GP
c) Thermomechanical
compaction
• Compactor in form of
reverse H-file at 8000 rpm
inserted with light force
parallel to master GP
• Rotating compactor heats
and condenses GP &
withdrawn while still
rotating
• Disadv- non-uniform
heating results in spiral-
shaped sections of
condensation
3.Thermoplasticized GP –
a) Obtura II-Warm Gutta Percha System
• GP pellets are inserted
into heated delivery
system.
• Heated to approx 185-
200°C
• Needle or applicator tip
designed to deliver
softened GP is introduced
into canal to junction of
middle and apical 3rd
• With needle in its position
GP is passively injected into
canal
• In 2-5 sec the softened GP
fills apical segment & begins
to lift the needle out of
tooth
• Controlled compaction with
prefitted pluggers adapt GP
• Additional amounts of GP
can be easily injected
b) Thermafil Obturation
• Use standardized plastic
points coated with α- GP.
• GP softened by heating &
then canal can be
obturated in 1 step.
• Special oven for warming
• Canal evaluation with
uncoated carrier
• Sealer applied, point
heated, inserted & carrier
cut.
• Radiograph to confirm
Gutta flow
• Non heated flowable obturation material
• Combines GP in powdered form (with particle size
30µm) and sealer
Gutta Flow
• Technique:
1. Gutta flow is layered into
apical part with final canal
tip
2.3.4. Master GP is wetted
with Gutta Flow and placed
in the canals one by one.
5. Backfill with Gutta Flow
6. Excess GP points cut with
hot instrument
7. Completed obturation
3. Gutta percha removal
Various techniques
1. Rotary removal
2. Ultrasonic removal
3. Heat removal
4. Heat and instrument removal
5. File and chemical removal
6. Paper point and chemical removal
1. Rotary removal
• Nickel Titanium files
(0.04 & 0.06) tapered
rotary – most effective
• Should be used with
caution in
underprepared canals
• Should accept
passively
• Divide the root into
thirds (1/3)
2.Ultrasonic removal
• Piezoelectric ultrasonic
system for rapid
elimination
• Produces heat that
thermosoftens GP
• Specially designed
instruments carried into
canal
• Float GP coronally into
pulp chamber,
subsequently removed
3. Heat removal
• Suitable for larger
canals due to larger
cross-sectional
diameter.
• Activate to red-hot,
plunge to coronal most
aspect of GP
• De-activate carrier-
freeze a bite of GP
• Withdraw instrument -
Bite removed
4. Heat and Instrument removal
• Employs heat and
hedstrom files.
• Hot instrument plunged
into GP to heat soften.
• 35,40 or 45 H-file quickly
but gently screwed into
softened mass.
• Poorly obturated canals –
in 1 motion also.
• Especially good when GP
extends beyond foramen.
5.File and Chemical removal
• Best option for small and curved canals
• Chloroform – fill pulp chamber with solvent
– Select appropriate size K-file
– Pick into chemically softened GP (creates pilot
hole.
– Initially size 10 and then serial use of larger files
– Continued till no GP particles on flutes of file.
– Initially coronal 1/3rd followed by middle and then
apical 1/3rd (prevents apical extrusion)
6. Paper point and Chemical
removal
• Wicking- drying solvent filled canals
with paper point
• Essential in removing residual gutta
percha
• Canal is first flushed with chloroform,
solution is then absorbed & removed
with PP.
• Once the PP are clean chloroform is
flushed and aspirated repeatedly –
creates back and forth turbulence
• Liberally flushed with 70% isopropyl
alcohol and wicked to remove the
residual GP.
Comparison
Protaper Hand Files SS Files
• Fewer instruments needed • Many instruments are needed
for preparation for preparation
• The canal can be prepared • Preparation is slow
with moderate speed
• ProTaper design increases
cutting efficiency • Cutting efficiency poor due to
• Canal curvature is well poor design
maintained • Transportation is very
common
• Consistent tapered
preparation coronal to apical • Tapered preparation always
with minimal foramen inconsistent with over
enlargement enlargement apically highly
probable
Comparison
Protaper Hand Files SS Files
• Less debris is extruded • Debris extrusion apically is
apically high
• Can be used in abrupt • Can be used in abrupt
curvature with prebent curvature but final preparation
instrument WHEN pathway never smooth
established by hand SS files
• Instrument separation is low • Instrument separation has not
due to good tactile feedback been a historic problem
