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