7
8
chamber. Press the appropriate start button for the left or right well. The
heating time varies depending on the size of the obturator.
The first beep indicates the obturator has reached the appropriate
temperature. The oven will hold the obturator at the right temperature and
beep every fifteen seconds, up to ninety seconds, as a reminder that the
obturator is ready. The oven will automatically switch off and begin to cool
after ninety seconds.
Remove the obturator by gently pushing on the holder button and
allowing the arm to raise up.
Placement of the Obturator
In teeth with multiple canals, place paper points in the unfilled canals to
avoid overflow of gutta-percha into these canals.
After removing the obturator from the oven, place it into the canal 1 mm
short of working length using a slow, smooth, continuous motion. To remove
the handle at the orifice level use one finger to steady the handle while
severing the shaft with a Prepi
®
bur or high-speed inverted cone bur.
Creating Post Space
The Prepi
®
bur is designed to facilitate post space preparation by creating
frictional heat that removes the plastic carrier and gutta-percha quickly and
efficiently. Its smooth, non-cutting head eliminates potential root perforations.
• Initiate post space with a Prepi bur, fluteless round bur or conventional
high speed round bur.
• Use the selected bur at 150,000-200,000 RPM and allow it to create
a 1 mm-2 mm dimple below the orifice.
• Attach the GT post drill to your motor and set the motor speed to
2,000 RPM.
• Use intermittent apical pressure to create your parallel post space.
The drill’s eccentric (angled) cutting tip will remove the plastic core
and filling material.
• Take the drill to the desired length. One pass may be sufficient.
• Irrigate the post space with sodium hypochlorite, and then water,
to remove any debris and filling material.
• Dry the canal with air or GT absorbent points.
• See GT Fiber Post directions for use for steps to appropriately place
the post.
Post Drill Sterilization
• Drills must be cleaned and sterilized before every use.
• Using distilled or de-ionized water, subject unwrapped instruments
to a pressure of 220 kPa (2.2 bar) for 20 minutes at a temperature
of 136 (± 2)°C, or dry heat sterilize them at 180 (± 5)°C for
120 minutes.
Retreatment of the GT Obturators
Occasionally, and despite good endodontic practices, a GT obturated
case may need to be retreated. GT obturators can be removed easily by
utilizing a variety of techniques. The most common is to drill down alongside
a carrier with a .04 or .06 tapered instrument at 2,000 RPM until it binds
in the plastic carrier. Frictional heat will loosen the gutta-percha and the
spiraling forces of the rotating instrument will grab the carrier and force it
coronally.
Instructions for Using the Obturator Oven
The GT Obturator Oven has been specially developed for heating GT
(Greater Taper) endodontic obturators for use in root canal therapy. Do not
use this oven for any other purpose.
Disinfecting the Obturator
1. Disinfect the obturator using full strength sodium hypochlorite solution
(bleach) in a dappen dish for one minute.
2. Use a 2”by 2” piece of sterile gauze to wipe the obturator with alcohol.
3. Dry the obturator for several seconds on a clean work surface to
allow evaporation of excess alcohol.
Instructions for Use
1. Plug the oven into a 110 VAC outlet. Then turn the oven on with
the power on/off switch located on the back. The green stand-by
indicator will light up.
2. Put both obturator holders in the upper position by pressing the back
of the holder (arrow up) and guiding the holder up with your finger.
3. After disinfecting the obturator and setting the rubber stop, place
the GT Obturator in the left obturator holder.
Regardless of what
working length you have determined, the rubber stop must be under
the holder.
Make sure the obturator is hanging straight, not at an
angle. The obturator must clear all sides of the heating chamber.
• Drills must be cleaned and sterilized before every use.
• Using distilled or de-ionized water, subject unwrapped instruments to apressure
of 220 kPa (2.2 bar) for 20 minutes at a temperature of 136 (± 2)°C, or dry heat
sterilize them at 180 (± 5)°C for 120 minutes.