Post on 16-Jul-2015
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GOALS of obturation
• TO FILL THE ENTIRE CANAL SYSTEM AND ITS COMPLEX ANATOMIC PATHWAYS COMPLETELY WITH NONIRRITATING HERMATIC SEALINGAGENTS.
OBJECTIVES OF CANAL OBTURATION
• Prevents percolation and microleakage of periradicular exudate into the root canal space.
• ) ) Prevents reinfection through good sealing of the apical foramina.
• ) ) Creates a favorable biologic environment for the process of tissue healing to take place.
Ideal root canal filling material requirments :
. ) ) Easily introduced
•) ) Seals laterally and apically
•) ) No shrinkage
•) ) Impervious to moisture
•) ) Bacteriostatic
•) ) Does not stain tooth
STEPS OF ROOT CANAL OBTURATION
• Rubber dam application
• Verify completion of the canal preparation.
• Check your working length, irrigate & DRY the canal.
• Fit the master cone (TUG- -BACK). BACK).
• Take radiograph. Take radiograph.
• Introduce the sealer cement.
• Condense the MC and accessory guttapercha.
• Take intermediate radiograph.
• Add more G.P points and remove access.
• Temporize the access and take final radiograph.
Master Cone
• (1) fit tightly laterally in the apical third of the canal (have good " canal),
• (2) fit to the full length of the canal (i.e., to the dentin- cementum junction or about 1 mm from the cementum junction or about 1 mm from the radiographic apex),
• (3) be impossible to force farther beyond the apical foramen.
LATERAL CONDENSATION
• Involves the compaction of the primary master cone and sealer against the apical foramen
• Condensing additional accessory gutta percha cones alongside the the master cone fills the remainder of the canal
Finishing
• GP to level with the CEJ
• Using cool end of plugger to vertically condense gutta percha at orifice
• Clean pulp chamber with cotton pellets soaked in alcohol
• Place temporary or final restoration
• Preferable to take radiograph before removing rubber dam
Radiographic evaluation of obturation
• Radiolucencies: Are there voids, indicating incomplete obturation?,
• Density: Is there uniform density from coronal to apical?
• Length: Does material extend to WL?
• Shape: Does fill reflect shape of the canal, tapered from coronal to apical?
Underfill
• An incomplete obturation of the root canal space with resultant voids
• Inadequate taper in preparation
• Improper spreader/cone placement
• Cannot be corrected by increased force
• An ideal root canal filling three-dimensionally fills the entire root canal system as close to the cemento-dentinal junction as possible
• •Teeth filled more than 2mm short of apex has poor prognosis underfillings with necrotic pulps
Causes
• o Dentin chips
• o Ledged canal
• o Curved canal
• o Master cone too large
• o Improper 3D shaping of canal in apical to middle third
Non-Surgical Retreatment
• Gain access to canal system and reach apical foramen via removal/bypass of obturation materials from canal
• - Patient usually has high outcome expectations - Requires greater clinical skill than original NSRCT treatment
• - Canal Obstructions – posts, separated instruments
Non-Surgical Retreatment. GP removal
. Quality of condensation
Shape of root canal
Length of obturation material – short fill, overextension, etc
Gates Gliddens, ProFiles, GPX
Removes GP t
Provides reservoir for solvent
Heat and hedstrom removal technique
Non-Surgical Retreatment
• Solvents.
• Chloroform
• Methylchloroform, Eucalyptol, Halothane, Xylene, Rectified white turpentine