Endodontics
Course Review
Enoch Ng, DDS 2014
Obturation
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Eliminates leakage from oral cavity or apical tissues into canal system
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Seals within the cavity any irritants that are not removed during cleaning/shaping
Influence on prognosis
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Poorly obturated teeth are usually poorly prepared
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Absence of pre-treatment PA lesion
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RCT without voids
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Obturation within 2mm of apex
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Adequate coronal restoration
When to Obturate
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Asymptomatic patient
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Temporary filling is intact
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Canal is prepared properly
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Canal is dry or can be dried
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Prefer to obturate on a different day than instrumenting – allow for healing to asymptomatic state
Obturation length
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Ideally at minor constriction (CDJ)
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Usually 1mm from radiographic apex (based on studies relating major foramen to apex and minor constriction)
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Extrusion of obturation material decreases healing prognosis and may result in patient discomfort
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Obturation shorter than 2mm from apex may slow healing, likely from remnant infected tissue left in that 2mm
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Overfill – total obturation of canal but excess material extrudes out beyond apical foramen
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Overextension – canal is NOT adequately sealed and material extrudes beyond apical foramen
Inadequate obturation
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Long obturation causes
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Excessive instrumentation beyond apex
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Excessive penetration of compacting instrument
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Excessive force during obturation
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Resorptive defect, perforation, strip perforation, zip
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Master cone too small
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Short obturation causes
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Dentin chips
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Ledged canal
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Curved canal
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Master cone too large
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Improper 3D shaping of canal in apical to middle third
