OBTUATION

PURPOSE OF OBTURATION

• a. Prevents percolation and microleakage of periapical exudate into the root canal space.

• b. Prevents infection by completely obliterating the apical foramen and other portals of communication.

• c. Creates a favorable environment for process of healing to take place.

• 1. To achieve total obliteration of the root canal space so as to prevent ingress of bacterias and body fluids into root canal space as well as egress of bacteriaswhich are left in canal.

• 2. To attain fluid tight seal so as to prevent bacterial microleakage.

• 3. To replace the empty root canal space with an inert filling material so as to prevent recurrent infection.

• 4. To seal the root canal space as well as to have coronal seal for long term success of root canal therapy.

Materials used for obturation

• Plastics: Gutta-percha, resilon

• Solids or metal cores: Silver points, Gold, stainless steel, titanium and irridio-platinum.

• Cements and pastes:– Hydron– MTA– Calcium phosphate– Gutta flow

Characteristics of an ideal root canal filling material1. Easily introduced in the canal.2. Seal canal laterally and apically.3. Dimensionally stable after being inserted.4. Impervious to moisture.5. Bacteriostatic or at least should not encourage bacterial growth.6. Radiopaque.7. Non staining to tooth structure.8. Non irritating.9. Sterile/easily sterilized.10. Removed easily from canal if required

Advantages of gutta-percha

• Compactiblity: adaptation to canal walls

• Inertness: makes it non-reactive material

• Dimensionally stable

• Tissue tolerance

• Radiopacity: easily recognizable on radiograph

• Plasticity: becomes plastic when heated

• Dissolve in some solvents like chloroform, eucalyptus oil, etc. This property makes it more versatile as canal fillingmaterial.

Disadvantages

• Lack of rigidity: Bending of gutta-percha is seen when lateral pressure is applied. So, difficult to use in smaller canals

• Easily displaced by pressure

• Lacks adhesive quality.

RC Sealers

Requirements of an ideal root canal sealer

• Should be tacky when mixed to provide good adhesion between it and the canal wall when set.

• Should create hermetic seal.

• Should be radiopaque.

• Powder particles size should be very fine, for easy mixing with liquid.

• Should not shrink upon setting.

• Should not stain tooth structure.

• Should be non-irritating to periradicular tissue.

• Should be soluble in a common solvent.

• Should not provide immune response in periradicular tissue.

• Should not be mutagenic or carcinogenic

• Should be bacteriostatic.

• Should set slowly.

• Should be insoluble in tissue fluids

Functions of root canal sealers

• As antimicrobial agent

• Fill the discrepancies between the materials and dentin walls

• As binding agent

• As lubricant

• Give radiopacity

• As canal obturating material

Zinc Oxide Eugenol Sealers

Root Canal Sealers Without EugenolKloroperka N-Ø Sealers