Griffin, GA...Sunday August 28, 1994
The proof of the puddin' is in the eatin'.
Kit Weathers and I have made a new video to enable you to sample the pudding of the STS( Successor To Sonics ) canal preparation device without actually buying one.
I wanted to see really how fast I could do a bunch of preparations.
So we set up a close up video camera in the 'Magic Endo Bus' and video taped the preparation of several teeth.
The verdict is up to you but I can tell you that IT WAS FAST.
As one of the attendees told me yesterday in Lynchburg, VA...'It really guts out a canal'.
But along the way we found out something else.
That it is also SAFE.
The reason is part of the STS system which moves the file in Linear Oscillation only about 0.8 mm at a rate of 500 strokes per second(Actually 250 up and 250 down).
I have told many of you in the "Automated Endo" class that there are two ways to break a Fine-Cut file.
You can twist it off or you can buckle it, get it stuck and pull on it.
Since the STS does not turn the file it cannot break it that way.
And since to buckle a file you have to push it beyond bowing it, which takes about 3mm, the STS does not push it that far.
Ergo, no breakage.
In the video, which is available on loan for a $10 deposit refundable toward the purchase of the STS, you can see for yourself some of the technical aspects of STS preparation.
Although it is still a good idea to take the course or to attend one of the AERG study group meetings listed on the back page, you can also buy the STS after seeing the video.
The total cost of the STS system including the Fine-Cut adapter is about $400.00.
There are some conditions, however.
Since the main part of the device is an electice tooth brush, once it is in your hands, I cannot take it back because the California Good Manufacturing Practices Act prevents me from selling it again. ( You surely wouldn't want to buy a used one would you? )
Another reason you might want to take a hands on training session with it is to cover yourself medico-legally although if you have been doing circumferential filing I see no radical departure from you existing technique.
As we get feedback from the users I will pass on the technique tips via this newsletter.
E-mail your comments to drjack@BetterEndo.com
Santa Cruz, CA...October 15, 1994
...and here are a few of them.
Not at all.
In the Fine Cut System, the flutes get farther apart as you move from tip to shank of the file and as you go from smaller to larger files.
When the inter- flute distance exceeds the up-and-down oscillatory motion of the STS, the flutes don't move far enought to do any cutting.
Simply hold the STS with the tip of the file about 3mm into the orifice and circumferentially file.
This gives you better access for your probing files.
If when you do this you can go further, do so.
You may find that you have reached very close to the apex in which case the prep is practically done.
This is important to avoid zipping and stripping.
Going through the sized to 30 can eliminate this problem.
It is also easy to control the depth since your hand is held steady and thus you can go closer to the apex with safety.
Some dentists are actually using it to prepare the apex as well.
Probe to the apex with a #15 hand file.
Set a rubber stop on an STS #15.
Insert the file to apical length with the STS running.
Once you reach the apex and begin moving in a circular motion, slowly withdraw the file.
Do this two or three times with the #15.
Then use a #20,inserting with the STS on until the file begins to bind near the apex, slowly withdraw while circumferentially filing as before.
Repeat with the #25 and #30.
This will give you a step back prep with no ledges,or aneurisms.
Getting a file stuck is of no consequence, as the handpiece simply moves up and down.
This same phenomenon happens when using sonics with circumferential filing because the filehas a negative rake on the way in and positive on the way out.
Each in stroke moves the file further in, and you hand tends to follow it in.
That includes zipping the apex if you go past the apex.
That also includes creating an aneurism( a bulge in the outside of the curve short of actual stripping) in the canal if you force a straight file around a curve.
The amount of up and down motion is insufficient to buckle the file.
And since it doesn't turn, it cannot twist off.
It is easier to handle.
If it cuts 25 to 50 times as fast as sonics, it also generates fifty times the debris.
Failure to irrigate can pack debris pretty hard and pretty fast.
Then it's ready at any time.
The adapter should then be removed turning with finger pressure only.
Remove the lock nut and sterilize it too.
Put a plastic bag over the STS, puncture the bag with the threaded end of the STS and put the lock nut back on until only about 1/8 inch of threads are visible, then put the adapter back on until it touches the lock nut.
Then adjust the angle of the water port on the adapter until it is at right angles to the on/off button on the STS handle.
Turn the lock nut counter-clockwise to lock the adapter back on.
This increases the amplitude of the motion.
But be careful because it is easier to buckle files this way.