Obturation Techniques Flashcards
What is the aim of Obturation?
establish a fluid-tight barrier to protect the
periradicular tissues from microorganisms that reside in the oral cavity.
What are the 3 purposes of Obturation?
- Prevent coronal leakage of microorganisms or potential nutrients to
support their growth into the dead space of the root canal system. - Prevent periapical or periodontal fluids percolating into the root canals
and feeding microorganisms. - Entomb any residual microorganisms that have survived the
debridement and disinfection stages of treatment, in order to prevent
their proliferation and pathogenicity.
What is required for a good 3D seal?
Adequate preparation is essential for adequate
obturation.
Root canal sealers are used in conjunction with a biologically acceptable semi-solid obturating material such as gutta-percha to establish an adequate seal of the root canal system.
The root canal systems need to be three
dimensionally obturated.
2 components of Obturation?
Core material and sealer
what are th ideal properties of Obturation material?
Easily introduced into the lot canal system
Should not shrink after being inserted
Should be bacteriostatic or at least not encourage bacterial growth
Shown not stain tooth structure
Should be sterile or easily and quickly steralized immediately before insertion
Should seal canal laterally as well as apically
Should be impervious to moisture
Should be radio-opaque
Should not irritate periapical tissue
Should be easily removed from the root cabal if necessary
purpose of root canal sealers?
- Fill in the gap between the dentinal wall and the core root filling
material. - Fill space between the core segments (depending on technique).
- Fill in irregularities within the canal system i.e. occlusion of
accessory canals and isthmi between canals.
Ideal properties for root canal sealer?
Should exhibit tackiness when mixed to provide good adhesion to the canal wall when set
Should be radio-opaque
Should be bacteriostatic or at least not encourage bacterial growth
Should not be soluble in tissue fluids
Should be soluble in a common solvent if it is necessary to remove it
Should establish a hermetic seal
Should be prepared in very fine powder so it can mix liquid easily
Should not stain tooth structure
Should exhibit slow set
Should not irritate periapical tissue
What is the most common sealer?
Zinc oxide euganol
And resin
brand name of ZOE sealer?
tubli-seal
Pros of ZOE?
long history
Absorbed if extruded
Slow setting time
Antimicrobial effect
Radio-opaque
cons of ZOE?
Shrinkage on setting
Soluble
Stain tooth structure Should
Negative affect bonding
how to remove excess ZOE?
pledget soaked in alcohol
Options for sealers?
Calcium hydroxide
ZOE
GIC
Resin
Silicone
Bioceramics
examples of COH?
Apexit
Sealapex
pros of COH?
Antimicrobial
Radio-opaque
Good tissue tolerance
cons of COH?
Soluble
Weakens dentine
Can crumble wen set
GIC and sealers during RCT?
Not really used now
pros of GIC?
Dentine bonding properties
High compressive strength
cons of GIC?
Minimal/no antimicrob8al effects
Difficult. Remove in retreatment
Reduce retreivability
pro of resin asa sealer?
Ling history of use
Adhere to dentine
Some adhere to core
No euganol
Slow setting
cons of resin for sealing RCT?
Some releases of formaldehyde when setting
Certain irritants reduce bind strength
May not bond more effectively than conventional sealers
Negatives of euganol from ZOE?
Redness, itching, or swelling
Difficulty breathing
Mouth sores
Burning sensation in the mouth
Throat tightness
Tongue swelling
In rare cases, anaphylaxis, a severe allergic reaction
Examples of resin for RCT?
AH plus
Diabetes
Epiphany
Real seal
examples of silicone for RCT?
Guttaflow 2
Roekoseal
pros of silicone?
Long working time
Consistency fills canal irregularities
Biocompatible/ bioactive
Nearly insoluble
cons of silicone for RCT?
Expand slightly on setting Soluble
Setting time inconsistent
Setting time delayed by sodium hypochlorite
pros of bioceramics sealers?
Biocompatible
Bioactive
Dimensionally stable during setting
Hydrophilic
Antimicrobial
Minimal resporptin
cons of bioceramics?
Relatively new, therefore little long-term evidence of effect on tx outcomes
Increased expense
Retretament challenging, especially when no GP core to length and were considerable thickness of sealer
how can gotta percha be placed?
Can be placed using lateral compaction, warm lateral or vertical compaction or thermoplastic injection techniques
pros of Gutta percha?
Plasticity
Ease of manipulation
Minimal toxicity
Radio-opacity
Ease of removal
cons of gutta percha?
No adhesion to dentine
1-2% Shrinkage on cooling
when heated
Becomes brittle if stored for
a long time
Resilon?
Thermoplastic synthetic polymer-based
(polycaprolactone polyester) root canal filling material
Pros of resilon?
Can be used as an alternative to gutta percha
When used with resin sealer may form monoblock
cons of resilon?
Sealing ability equivocal
Sealing ability reduced by NaOCl
Formation of monoblock controversial
Obturation techniques?
Single Cone
Cold Lateral Compaction
Warm Vertical Compaction
Warm Lateral Compaction
Carrier Based Thermo-compaction
Plasticised Gutta Percha Injection
Hydraulic Calcium Silicate Apical Barriers
What is the most common Obturation technique used in the uk?
Cold lateral compaction
cold lateral compaction technique?
- Preferred technique in Aberdeen Dental
Institute and most UK dental schools. - Master cone corresponding to the final working length (FWL) and canal shape is chosen, coated in sealer and compacted
laterally with finger spreaders. - Accessory cones will be used until the
obturation is complete. - This technique does not produce a
homogeneous mass and the core material and the accessory cones remain
separated. As a result, sealers should be
used to fill in the gaps. - Excessive force whilst compacting GP
may lead to root fracture
Tips for success with cold lateral compaction Obturation?
- Always ensure a friction fit of the master apical point at the working length to confirm
snugness of fit and resistance to displacement during compaction. - Manufacturing errors in GP points can create significant variation in size. If the point is short or
long, always try a second point before doubting your instrumentation. GP size-checkers are
handy tools to assess the apical diameter of standardized and non-standardized points. - Mark the master cone to ensure it is not forced beyond or withdrawn from the apex as the
spreader is placed and removed. - Measure and place a stopper on the spreader to gauge the depth to which the accessory GP
point will be placed, ideally the first should be within 1–2 mm of FWL. - Ensure the accessory cones are matched to (or slightly smaller than) the spreader size
Name the type of file?
What type of filing system to we use at iod?
Pro-taper ultimate
single core technique?
Use of a size-matched greater taper cone to fit the prepared canal precisely.
* Often used following specific filing systems.
* Reliant on sealer and may not adequately obturate the canal in 3 dimensions. Nonetheless, the apical portion should be well fitting.
* Some add accessory points AKA single cone + technique.
* Advocated with bioceramic sealers which are capable of
sealing potential voids.
* Favoured by many GDPs as relatively quick and simple technique with relatively low cost (increased cost if bioceramic
used).
Warm vertical compaction technique?
- A master cone corresponding to the correct
working length and canal size is chosen. The
cone should resist displacement at this length. - Once confirmed, the cone is coated with
sealer and placed in the canal and compacted
vertically using a heated plugger until the
apical 5–7 mm segment of the canal is filled. - The canal system is then backfilled using
molten gutta percha from a commercial
heating device, such as ‘System B’ or
‘Elements’.
When is elements IC used?
Warm vertical compaction
designed to be used with the Continuous Wave warm vertical condensation technique
plasticised gutta percha injection?
- Theoretical benefit of improving obturation as the material can flow
within the canal space. - Injection techniques alone without a cold cone or plug of GP at the
apical constriction are not advised due to difficulties in length control. - Heated systems include Obtura III, Ultrafill 3D, Calamus, Elements and
HotShot - Guttaflow is triturated GP mixed with resin sealer (di-polyvinyl siloxane)
in an amalgamator to form a cold flowable matrix. The matrix is
injected into the canal and a single master cone is placed to the
working length. The use of a master cone within the GP sealer is
advocated.
How is plasticised gutta percha injection carried out?
During a root canal procedure, the tooth’s damaged pulp is removed and the canals are cleaned and disinfected
The thermoplastic gutta-percha is heated and compressed into the tooth’s canal
The canal is sealed with adhesive cement
Benefits of plasticised gutta percha injection?
Increases the density of the gutta-percha in the apical region
Provides greater fluidity in the lateral ducts
Produces a homogeneous mass in the whole duct
Reduces the stress applied to the root
Carrier based thermo-compaction?
Warm GP or ‘Resilon’
-coated plastic or gutta percha core carriers are inserted into the canal to the working length.
* A blank core must be inserted into the canal before
obturation to verify length, taper and fit.
* Following this, the canal should be lightly coated with sealer and the point is placed in an oven to heat before
being carefully but quickly inserted within the canal.
* This technique is fast, but true length control is lacking and there is a risk of extrusion of both sealer and GP. It
is also easy for the GP to ‘strip’ off from the carrier
before being fully inserted, leaving an inadequate fill with voids and contact of the carrier with the root wall
rather than sealer and GP.
* Examples include: Thermafil, Successfil, Simplifill and
Guttacore
Types of gutta percha?
- Solid core GP points: Available as standardized and non-standardized points
- Thermomechanical compactable GP: A type of gutta percha that can be compacted
- Thermo plasticized GP: Available in injectable form
- Cold flowable GP: A type of gutta percha that can flow
What is gutta percha core?
a core filling material used in endodontics to fill root canals. Gutta percha is a natural plastic that’s extracted from trees in Southeast Asia. It’s the most widely used core filling material.
When to use an apical barrier?
need a wide and straight canal
Indicated when obturating teeth with open apices
How is the rest of the canal filled after the apical barrier technique?
Filled with injection technique
apical barrier technique?
- MTA or HCSC is compacted by hand to fill the
apical 3–5 mm of the canal. Initially it is a
good idea to create a 1–2 mm plug first at the
apex and then check this radiographically. - Once this has been placed satisfactorily,
further MTA can be placed coronal to this. - This is often only possible in wider, straighter
canals. - The remainder of the canal system can then
be filled with an injection technique
Other materials used for Obturation?
Russian red
Silver points
Russian red obturation technique?
Resorcinol-formaldehyde resin). Providers
believe pulp tissue will be fixed and bacteria destroyed apical to the level of resorcinol-formaldehyde resin placement. Canals are frequently not instrumented or to their full length. Sets brick hard, no known solvent, therefore irretrievable. Can be radiolucent. Stains dentine red.
Silver point obturation technique?
No-longer used due to: corrosion which
causes which cause argyrosis and periradicular inflammation and staining of tooth structure, lack of plasticity, incompatibility with posts
What happens of the GP is overextended?
GP extends grossly beyond the apex. This reflects both poor apical fit of the cone and poor obturation technique. These cases may fail and retrieval of
overextended GP is not easy.
what happens of the gap is overfilled?
GP is well condensed but radiographically beyond the apex. This may be a
reflection of overzealous apical preparation and loss of apical architecture, it can occur when there is an immature apex or external inflammatory resorption. There is evidence that a more aggressive apical preparation may have a more favourable healing but the clinician must always aim to remain within the canal and preserve the apical constriction.
What happens of the GP is under extended/underfilled?
GP is short of the apex with or without voids. Indicative that the canal space has not been adequately shaped and/or cleaned, as such bacterial colonies may remain within the root canal system and disease can persist.
How to prevent extrusion?
- Meticulous length control is important during instrumentation. Instruments should not be forced apically and rotary instruments should not be used for more than 2–3 ‘pecks’ at the WL to prevent
overpreparation or zipping. - Ensure tight ‘tug back’ fit of master apical cone.
- If in doubt always verify the WL. The use of a cone-fit radiograph with the master GP in place is invaluable if uncertain If there is a discrepancy with WL and the length the GP fits to, do not obturate.
- If the GP does not seat to WL it may be that two canals coalesce (classically mesial roots of lower molars). To ensure adequate obturation of both canals, fill the first. Cut the tip from the GP of the
second canal with a scalpel until the GP abuts the first GP point at the correct WL - Use plasticized techniques with caution and take extra precaution when working in close proximity to significant anatomical structures.
- If using warm or plasticized techniques, consider using instrumentation techniques that allow controlled obturation with matched greater taper continuous or variable taper points.
What radiograph would you take before obturation?
Cone-fit radiographs
what to do if GP does not eat to the WL?
it may be that two canals coalesce (classically mesial roots of lower molars). To ensure adequate obturation of both canals, fill the first. Cut the tip from the GP of the second canal with a scalpel until the GP abuts the first GP point at the correct WL
Contraindication to obturation?
- Active ongoing periapical infection
- Suspicion of extrusion of irrigant
- Irregularities of measurement / apical fit
- No MAC radiograph
- Insufficient time
- Limited compliance
