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6. 5 HOW TO USE
6. Measuring the Working Length.
1) When inserting the K-file (or reamer) into the root canal, the meter
needle on the display panel swings to the right and reaches the
working length (W.L.) position, and, at the same time, the buzzer
sound (intermittent) starts. This position is to be noted as the
working length.
The position indicated as W.L. on the display panel should be
considered as a criterion for the working length. The actual
working length differs depending on the root canal conditions.
W.L shown on the panel should be the point about 0.7mm less
distance to reach the apical foramen.
WARNING
1) If the abnormality is felt on the position which the meter needle shows,
confirm the position of the K-file (or reamer) by the x-ray.
2) The buzzer sound tells when the K-file (or reamer) reaches the working
length (W.L.). However, not only relying on the buzzer sound, always confirm
the indication of the meter needle on the display panel also.
CAUTION
When the K-file (or reamer) is moved farther into the root
canal, the meter needle on the display panel reaches the
APEX, at the same time, the buzzer sound becomes a
steady continuous sound. When determining the working
length from this position, it should be about 0.7mm shorter.
Watch discreetly the meter needle on the display panel,
as it has very high sensitivity in the vicinity of the apical foramen (APEX).
(Refer to the drawing on the needle position, though it depends on cases.)
3) Mark the working length on the K-file (or reamer)
Move the rubber stopper down to the working length
by using pincers.
4) Pull the K-file (or reamer) out of the root canal and
measure the distance to the position of the rubber
stopper with measuring gauge.
5) Please determine the working length in view of your procedure.
K-File (or reamer)
Rubber Stopper
Measuring Gauge
Pincers
6 OPERATIONS
