Obturation Flashcards
What are the goals of obturation?
- Eliminate ALL AVENUES OF LEAKAGE from the oral cavity INTO the ROOT CANAL SYSTEM or OUT OF the ROOT CANAL SYSTEM INTO the PERIODONTAL TISSUES
- Seal within the RC system any irritants that cannot be fully removed during canal cleaning & shaping and prevent their leakage out to the peri-radicular tissues
What are the obturation materials?
gutta percha
sealers
What is gutta percha?
–Can be softened by heat and solvents
–If heated sufficiently, will change phases
–Following softening SHRINKS
–GP by itself DOES NOT SEAL
–Must consider SEALERS
What is the phase of the gutta percha in lab?
beta phase
Until Bio-Ceramic, Bio-Active Sealers came into play, NO SEALER was ideal and ALL SEALERS:
- shrank upon setting
- dissolved in body fluids over time
- BUT now we have better sealers
What are the properties of bio-ceramic sealers?
- Do NOT shrink
- Do NOT dissolve
- Are BIO active
What is the standard of care for RC obturation?
- GP positioned 1 mm. short
of the canal exit - Totally filled with gutta percha and sealer (no VOIDS)
- Radiographic appearance of a
dense filling - Avoidance of gross overextension into the peri-apical tissues (GP and Sealer)
- Minimal Sealer beyond apical constriction
- No under-fillings in the presence of a patent canal
When are you ready to obturate?
- must be free of all signs and symptoms
- tooth is cleanded and shaped
- tooth is isolated to prevent contamination
If the patient is still in pain or the original symptoms have not abated, obturation of the RC system will…
NOT resolve the patient’s symptoms
What are the acceptable obturation techniques?
- Cold Lateral Compaction of Gutta Percha
- Hydraulic Obt Technique
- Warm vertical compaction
_________ is the secret to CLC-GP obturation success
COMPACTION
Carrier-based techniques (Thermafil ®) include?
– Carrier-based thermoplasticized
– Carrier-based sectional thermoplasticized
– RETX and posts a proble
What is cold lateral compaction (CLC-GP)?
Finger Spreaders are used to compact the MC gutta percha in the canal to create space for more Gutta Percha accessory cones to accomplish a dense fill and thin film of Sealer on the canal
- use 02.25 GP cone (RED)
What are the steps of cold lateral compaction?
- Final Irrigation
- Dry canal with paper points
- master cone is fitted (gutta percha)
- finger spreader is inserted to 2 mm short of working length
- spreader is rotated and removed and an accessory cone is placed
- process is repeated
What gutta percha cone is used in hydraulic obturation?
.04 GP cone
What gutta percha cone is used in cold lateral compaction obturation?
02.25 GP cone
Should the canal be dry or wet for the hydraulic obturation?
wet
How do you know if the master cone (gutta percha) fits?
Properly fitted cone has an intimate fit at WL with NO SPACES and no crinkling
How do you know if the master cone (gutta percha) is too small?
Cone is too small in diameter and distorts (crinkles) near apex
How do you know if the master cone (gutta percha) is too large?
Cone is too large coronally or canal taper is insufficient and will not seat at WL Black Arrow indicates level of binding
The ______________________ is our last chance to correct a problem easily
Master Cone Radiograph
Master cone (gutta percha) must NOT be able to be pushed beyond…
working length
What is the hydraulic technique for obturation?
- Select an .04 GP Cone and fit to WL & Radiograph
- Final Irrigation EDTA 17% & 8.3% NaOCl
- Dry canal with paper points
- Use a “double coat” technique on the Master Cone
- Place GP gently in the root canal
- May dart additional GP cones in irregular (wide) canals p.r.n.
- Sear off as per CLC-GP technique.
When searing off the gutta percha how long should you heat the instrument?
- until it turns red
- then wait 5 seconds before burning it
How do you sear the gutta percha?
- sear it with the plugger
- compact it down to the CEJ
- if you push too hard it can go through the apex
What do you do with a WIDE canal during the hydraulic technique?
- In a Type II canal, you pick the easiest canal to fill to WL; the second canal will merely merge into the 1st at some point short of WL
How do you make sure the master cone is at the working length?
take a master cone radiograph
Why do you take the gutta percha to the CEJ?
tooth will be discolored if you leave gutta percha in the pulp chamber
How do you control the apical constriction?
Do Not take any instrument larger than your patency file beyond WL
What is the best type of sealer to use with gutta percha?
Bioceramic (BC) sealer
When can you obturate?
when the canal is dry and patient has remained asymptomatic
Lateral compaction needs _____ finger spreaders (COMPACTION)
Blue
Hydraulic obturation technique uses an ___ GP cone and BC
sealer
.04
Sear GP below the ____, clean the pulp chamber and seal the canal with GI
CEJ
What is the composition of gutta percha?
- Trans-Polyisoprene (an isomer of latex)
–Gutta Percha
–Zinc oxide
–Waxes/resins/coloring agents
–Metal Sulfates
Why are silver points beneath the standard of care?
- Round peg in irregular hole
- Corrodes when sealer washes out (silver oxide)
- May stain both tooth & gingiva (Amalgam or silver Tattoo)
Why is Paraformaldehyde-containing pastes beneath the standard of care?
*N-2 (Sargenti Technique)
*Potential for great damage
*Proven Carcinogen
*Legal Precedent (Liability)
Firm pressure is required for dense fill but excessive force of compaction (CLC-GP or WVC-GP) can cause…
iatrogenic fracture of root
What does the ideal sealer have?
- Compatibility
- Inertness
- Tissue Tolerance
- Inexpensive
- Malleable
- Relatively easy to work
- Useful in MANY techniques
- Dimensional Stability ???
- Resistant to Dissolving ???
What are the negatives of sealer?
-Notoriously Poor Seal
-Expands & Contracts with:
-Solvent
-Temperature
-Will also change phases with sufficient variation in temperature (Amorphous Melt is NOT what you want to depend upon in RCT)
