Fractured tooth
Leakage through a branch canal
Fractured tooth will cause electrical leakage and an
accurate measurement cannot be obtained.
A branch canal will also cause electrical leakage.
Re-treatment of a root filled with gutta-percha
The gutta-percha must be completely removed to eliminate
its insulating effect. After removing the gutta-percha, pass a
small file all the way through the apical foramen and then
put a little saline in the canal, but do not let it overflow
the canal opening.
Crown or metal prosthesis touching gingival
tissue
Accurate measurement cannot be obtained if the file touches
a metal prosthesis that is touching gingival tissue.
In this case, widen the opening at the top of the crown so
that the file will not touch the metal prosthesis before taking
a measurement.
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How to use
6
Fracture
Branch
Gutta-Percha
Crown