Endodontic Materials: Root canal irrigants and medicaments

Endodontic Materials:

Root canal obturation materials1Obturating materialsAfter cleaning and shaping of canals, they are filled.Ideal properties of root canal filling materials:AntimicrobialBiocompatible.Good flowAdhesive in natureDimensionally stableNot affected by moistureRadio-opaqueGood handlingEasily removed, post prep or retreatDoes not stain dentineCheap

2Gutta PerchaGutta percha Isoprene (C5H8) is one of the oldest and most common root filling material in use today. A natural latex (rubber) produced from a genus of tropical trees

Polymers of isoprene:Cis-natural rubberTrans-gutta percha.

3Gutta percha points used in clinic consists of:Gutta percha 20%Zinc oxide 60-75%Metal sulphides, waxes, resin, opacifiers

Gutta percha is available in 2 phases; Alpha and Beta.

44Gutta percha taken from trees is the Alpha phase.Gutta percha in points used in the clinic is the Beta phase.Both phases differ in Melting temperature, volumetric changes and flow characteristics when molten.5

6Gutta perchaAdvantages of gutta percha:BiocompatibleDimensionally stableCompactable Easily removedCheap Disadvantages of gutta percha:Does not adhere to dentine Lacks rigidity

7Metal pointsSilver (gold, tin, lead and titanium have been used)Introduced in 1930sSilver preferred due to antibacterial effectRigid, unyieldingImpossible to adapt to canalsPoor seal as canal not commonly circular in shapeCorrosionDifficult to remove for postTitanium- biocompatible and avoids corrosion8Silver Point Failure

99SealersSealers are used in association with Gutta percha. Functions of sealerCementing (luting, binding) the core material (gutta percha) into the canal.Filling the discrepancies between the canal walls and core materialActing as a lubricant to enhance the positioning of the core filling materialActing as a bactericidal agent10Root canal sealersMost sealers are toxic when freshly mixedToxicity substantially reduced when setMost sealers are absorbable to some extent when exposed to tissue fluidIdeally sealer should flow backwards out of the canalHowever, no evidence that apical extrusion reduces success rate providing preparation and obturation are meticulous11Zinc-oxide eugenolGrossmans, TublisealAntibacterialRadio-opaqueSlightly toxic when freshly mixed.Good flow and working timeDoes not adheresoluble

12Calcium hydroxide based sealersSealapex, ApexitRadio-opaqueSolubleBiocompatibleAntimicrobialDoes not adhere

13Resin based sealersAH26, AH Plus, Endorez, Epiphany, RealSeal.AdhesiveAntibacterialToxic when freshly mixedShow setting shrinkage when set

14Glass-ionomer based sealersKetac Endo and ActiV GP sealer.Mildly antibacterialAdheres to dentineSlightly solubleUnset GIC is cytotoxic but when set this reduces with timeVery difficult to be removed

15Silicone based sealersRoekoseal sealer.Slightly expands when set. Addition type silicone.GuttaFlow is Roekoseal sealer with added gutta percha particles.Does not adhere to root canal.

16New root canal filling materialsResilon: resin-based cones. Similar in appearance and handling to gutta percha cones. Used with any resin-based sealer.Endorez cones: resin-coated gutta percha. Used with endorez sealer or any other resin-based sealer.ActiV GP: glass ionomer coated gutta percha. Used with glass ionomer based sealers.17Retrograde root filling materialsIdeal propertiesSeals apexBiocompatibleEase of handlingMoisture and blood tolerantLow solubilityRadio-opaqueGood tissue responseBonds to dentine

18AmalgamCorrosionApical inflammationPoor sealing abilityMercury toxicity19IRMModified zinc oxide-eugenolSeals better than amalgamNeed high powder to liquid ratio to decrease toxicity and solubilityShort working time20Super EBAModified zinc oxide-eugenolHigh compressive and tensile strengthNeutral pHLow solubilityNot affected by bloodGood tissue response21CompositeProblems with moisture controlSome good results in sealing ability but further work required22Glass Ionomer CementsBonds to tooth substanceBiocompatibilty (Toxicity reduces when set)Some antibacterial propertiesSeal superior to amalgam23New materialsDiaket (Tricalcium phosphate paste)Polyvinyl resinGood tissue response?cementum formingMineral Trioxide aggregates (MTA)Seals better than amalgam or super EPANot adversly affected by bloodMarginal adaptation better than amalgam, IRM or super EBA?cytotoxicityLaserHydroxyapatite24MTAMineral trioxide aggregate:Pulp cappingPulpotomy and partial Pulpotomy.Perforation repair Internal and external resorption.Nonsurgical apical closureSurgical root end filling

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