OBTURATION Flashcards
AIM OF OBTURATION
- produce a hermetic seal of the root canal system apically, laterally and coronally
Objectives of obturation (Sundqvist & Figdor)
- Seal against ingrowth of bacteria from the oral cavity
- Entomb residual microorganisms
- Prevent percolation of tissue fluid into the pulp space.
Grossman’s criteria of good obturation material:
- Inert
- Dimensionally stable
- Non-allergenic
- Antibacterial
- Non-staining
- Adheres to dentine
- Radiopaque
- Able to be compacted
- Provide a bacterial tight seal
- Can be removed.
WHAT BACT SURVIVE IN AFTER OBTURATION
Aim- produce a hermetic seal of the root canal system apically, laterally and coronally.
Only certain bacterial survive and proliferate in the harsh environment of the root canal system. E faecalis, streptococci, candida and actinomyces (Sundqvist) are found to be persistent and commonly observed in failed endodontically treated teeth.
The following criteria (Strindberg 1956, Bender et al. 1966) were used to define successful endodontic treatment:
- Radiographic evidence of an intact lamina dura and normal periodontal ligament space around the root surface
- Absence of pain or swelling of endodontic origin
- Disappearance of a draining sinus if it had been present prior to the endodontic treatment
- No loss of function
- No evidence of tissue destruction
Obturation technique:
- Lateral condensation (gold standards)
- Warm vertical compaction
- Carrier core system
- Hybride technique
Materials for obturation
- Gutta percha (gold standards)
- Resilon- polycaprolactone thermoplastic material. Similar handling to GP. Bonds chemically to radicular dentine forming best seal -> no longer used
- MTA- mineral trioxide silicate.
- Silver points
- Paste
composition of GP
- 20% gutta-percha (matrix)
- 66% zinc oxide (filler)
- 11% heavy metal sulfates (radiopacifier)
- 3% waxes and/or resins (plasticizer).
types of sealers
AH26+ sealapex Epiphany SE Activ GP MTA sealer
content of AH26+
epoxide paste contains radioopaque fillers and Aerosil.
Contains: polymers, aerosil, and the pigment
content of sealapex
- Sealapex contains calcium oxide and has the ability to induce hard tissue formation at the apex after root canal obturation (Holland & Souza 1985).
- The barium sulphate in its formulation has been replaced recently with bismuth trioxide, leading to a marked improvement in radiopacity (Tanomaru-Filho et al. 2008).
content of Epiphany SE
- Epiphany SE (Self-Etch) is a component in the Epiphany/Resilon system, developed with the goal of promoting better adhesion between the filling materials and the root canal walls.
- Epiphany contains several methacrylates in its formulation (Ungor et al. 2006) and has been recently replaced by Epiphany SE, which does not require a primer.
content of The Activ GP system
• The Activ GP system (Brasseler, Savannah, GA, USA) includes glass– ionomer-coated gutta-percha cones and a glass–ionomer- based sealer. In terms of apical leakage, this material behaved similarly to AH Plus after vertical condensation (Monticelli et al. 2007)
BIOCERAMIC CEMENTS
Eg: EndoSequence BC Sealer
Composition: Zirconium Oxide, Calsium silicate, Calsium phosphate, Calcium Hydroxide, Water (20%- also setting agent), Filler, thickening agent,
Properties: Biocompatible, non-toxic, non-shrinking, clinically stable, Alkaline, radiopaque, antibacterial, sets by forming hydroxyapatite between dentine and cement.
Cons: difficult to penetrate sealer for retreatment purposes- which may affect prognosis for retreatment cases when patency can not be re-established.
Pros: adheres chemically to dentin decreasing marginal leakage and gaps. Nanoparticles allows for deeper penetration into the dentinal tubules. Chemical bonding and nanoparticle nature improves fracture resistance of endo treated root. Sets by forming hydroxyapatite bond between dentin and cement. Water from dentin sets BC sealer
importance of apical seal
Oliver & Abbott (2001) has demonstrated that virtually all (99.5%) of the clinically placed root canal fillings did not provide an apical seal against fluid penetration; the presence of leakage did not affect the outcome of the endodontic treatment.
Failure to achieve total filling of the root canal only represents a potential for future bacterial contamination, survival and proliferation, but does not proofs unsuccessful endodontic treatment. The success of endodontic treatment will ultimately depend on the host response and its adaptation to both apical and coronal leakage that occurs following endodontic treatment.
