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3.
EMR (Electric Measurement of Root canal
length)
Accurate measurement cannot be obtained with the root canal conditions
shown below.
Root canal with a large apical foramen
Root canal that has an exceptionally large apical foramen due to a lesion or
incomplete development cannot be accurately measured. The results may
show shorter measurement than the actual length.
Root canal with blood overflowing from the opening
If blood overflows from the opening of the root canal and contacts the gums,
this will result in electrical leakage and an accurate measurement cannot be
obtained. Wait for bleeding to stop completely. Clean the inside and opening
of the canal thoroughly to get rid of all blood, and then make a measurement.
Root canal with a chemical solution overflowing from the opening
An accurate measurement cannot be obtained if some chemical solution is
overflowing from the canal opening. In this case, clean the canal and its
opening. It is important to get rid of any solution overflowing the opening.
Broken crown
If the crown is broken and a section of the gingival tissue intrudes into the
cavity surrounding the canal opening, contact between the gingival tissue and
the file will result in electrical leakage and an accurate measurement cannot
be obtained. In this case, build up the tooth with a suitable material to
insulate the gingival tissue.
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.
