Kenneth Koch, DMD
Dennis Brave, DDS
Two years ago when we addressed the topic of increased productivity (An Endodontic Genie), we concentrated on one topic - the .06 fully tapered preparation. We remain steadfast in our support of a fully tapered .06 taper preparation. This year we offer two additional tips for your consideration. The first is the concept of using a rotary file that has maximum cutting efficiency and is therefore a more efficient instrument. The second topic is one that has been rarely discussed - the single use of rotary files and how it affects office productivity from the assistant’s point of view. Let’s begin with a more efficient instrument.
We have known for years that a reamer is a far more efficient cutting design when compared to that of a file. The challenge for mechanized reamers historically has been to stay centered in the canal, i.e. avoid transportation. Consequently, the early generations of rotary files had noncutting tips and radial lands. It was this combination of noncutting tips and radial lands that kept the files centered. Although there were some advantages, there are distinct disadvantages associated with their use.
Rotary files with radial lands have a greater mass of metal that results in a stiffer file. Additionally, the excess of metal behind the cutting edge significantly decreases the cutting ability of the instrument. This is true regardless of the rake angle on the cutting edge. Furthermore and, in our opinion, the most significant is that files with radial lands (full or recessed) require a significantly greater amount of torque to spin the files. This is because the radial lands contact the canal walls and thereby dramatically increase the lateral resistance.
The quest for a rotary file that will display maximum cutting efficiency yet remain centered in the canal has been solved with the introduction of the EndoSequence file by Real World Endo and Brasseler USA. Let’s look at some of the features of this instrument.
What makes the EndoSequence file so special is that it is not a file - it is a reamer!
The triangular shape of the Sequence file means that there are no radial lands present on the instrument (true reamer). This contributes greatly to increased cutting efficiency. Even more significant is that this instrument is the first mechanized reamer that stays centered in the canal. This is achieved through the use of alternating contact points, or ACPs, that keep the file centered while not allowing the file to become totally engaged along its shank (Figure 1).
An additional feature of the Sequence file is that it has been electropolished. In fact, it is the only fully tapered file in North America that is electropolished (Figures 2 and 3). This process not only removes micro defects that often remain after traditional polishing, but it also adds sharpness to the cutting edge. Naturally, files with a sharper edge will be more efficient that those with a dull or rounded edge.
The net result of combining a true reamer design with a constant .06 taper is the most efficient instrument yet created in rotary endodontics. Endodontic practices that are using this file (in combination with laser-verified gutta percha) report an increase in production of one to two more cases completed per day per clinician. Talk about increased profitability!
The other topic is one that has remained off the radar screen. This is the single use of rotary files and its impact on office efficiency. While we certainly understand that rotary files are not cheap and that most clinicians would like to use them multiple times, the critical issue is cyclic fatigue.
Cyclic fatigue is one of the two reasons why rotary files separate (the other is excessive torque). This can happen regardless of the manufacturer. But the greater problem is this: Cyclic fatigue is insidious because you cannot see it like one can see excessive torque (unwinding). Consequently, the only way to control cyclic fatigue is to discard the files after use in a single case. The experience of having a file break simply because you used it too many times is something that can be and should be avoided. Nevertheless, there is another aspect to the single use of rotary files, and this is from the assistant’s perspective.
Since the introduction of the single-case-use of EndoSequence files in multiple offices, we have received numerous calls from assistants telling us how this has changed their office experience. We would like to relate some of their observations.
The first change they notice is the increase in productivity. Their doctors are completing cases more quickly (more single-visit endo), while the patients are expressing gratitude because they do not have to come back. The entire office from front desk to treatment room seems to be more cheerful (their word, not ours).
The second change is that the assistants find that they personally have less stress than they had previously when they had to be concerned about monitoring the number of times a file was used. This is especially true in those practices that have multiple doctors performing endodontic procedures. There can be a lot of stress on an assistant if a doctor breaks a file after it has been sterilized.
As a result of less stress, every assistant has said to us that they feel more effective working with the doctor and in the office. Also, single use results in a significant reduction in time spent with the ultrasonic baths and in the sterilization room. Most assistants state that their time is better spent with the patient in the treatment room.
Another positive aspect to single use (and one which escaped us) is that the assistants report that their doctors also seem to work with less stress. Every assistant we have spoken to stated that his or her doctor no longer has this overwhelming concern about “Is this file going to break?” or, “Have I used this file too many times?” We did not anticipate such a significant change in doctors’ behavior, but multiple assistants have repeated this point. Its importance is quite simple. The net result of a smoother, more efficient practice is increased profitability.
In this article, we have offered a few pointers that we feel can significantly increase your profitability in endodontics. We would like you to continue to prepare your canals with a constant .06 taper using the most efficient instrument available - the EndoSequence file - and please get in the habit of discarding them after a single difficult case (especially molars). If you take these tips to heart, we think you will be very pleased at the increase in your production as well as the increase in office morale. Certainly, we will continue to offer tips and suggestions and, as usual, we will continue to give you “Just the facts, nothing but the facts.”
Dr. Dennis Brave is a diplomate of the American Board of Endodontics and a member of the College of Diplomates. In endodontic practice for 27 years, he was the senior managing partner of a group specialty practice. Dr. Brave, formerly an associate clinical professor at the University of Pennsylvania, currently holds a staff position at The Johns Hopkins Hospital.
Dr. Kenneth Koch is the founder and past director of the program in postdoctoral endodontics at the Harvard School of Dental Medicine. In addition to having maintained a private practice limited to endodontics, he has written numerous articles on endodontics and maintains a faculty position at Harvard.
They can be reached at Real World Endo (866) 793-3636 or through www.realworldendo.com.