Real world endodontics

Sept. 1, 2003
High tide, low tide. New moon, full moon. This is change and it is a natural phenomenon. We cannot prevent it, nor do we want to prevent it. Change is good, in nature and in dentistry. The "winds of change" are upon us, and this is particularly true for endodontics.

Products and techniques that will make your endodontic experiences better!

By Kenneth Koch, DMD, and Dennis Brave, DDS

High tide, low tide. New moon, full moon. This is change and it is a natural phenomenon. We cannot prevent it, nor do we want to prevent it. Change is good, in nature and in dentistry. The "winds of change" are upon us, and this is particularly true for endodontics.

Historically, endodontics has had extended periods of dormancy when change was not prevalent. However, in this next academic year of 2003-2004, we will experience significant change in endodontics. Quite honestly, it is about time.

In this article, we want to highlight some of the potential changes (philosophical and literal) that we see coming to endodontics. The potential changes range from the idea of disposable endodontic products to the concept of a true hermetic seal when obturating the canal. Certainly not the least among the changes is the issue of making endodontics not only better, but also simpler. The more sophisticated a concept, the simpler it should be. This rationale is a foundation of many cultures, but has yet to take hold in North America.

Recently, we had the pleasure to attend and lecture at the "Roots Summit" in Anaheim. During the course of the meeting, there was a discernible buzz about where endodontics is headed. A topic that was addressed by multiple speakers was asepsis and single-use items in endodontics. It is about time that endodontics became as dedicated to single-use items as other aspects of dentistry. We find it incredulous that many patients will pay more than $1,000 for a root canal, yet they do not receive the dignity of having their own rotary instruments. When you really think about it, this is fairly outrageous. How would you like to have an implant that previously was in someone else's mouth? We don't think so! Look for the introduction of more single-use items in the near future.

However, when we think of single-use items in endodontics, we have an obvious question. What has been the major hindrance to the single use of nickel titanium rotary files? The easy answer is cost. Most clinicians feel rotary files are too highly priced and, consequently, want to use them multiple times. We firmly believe that you will soon see lower priced rotary files come to the dental marketplace — not lesser quality, just less pricey. Dental companies may not like to hear this, but it is just a matter of time. In fact, we believe dental companies can make better files at a lower price — if they seriously want to do so. It is all about margin and price points. Time will tell.

Another topic of discussion is the need for an open mind, both clinically and in academics. This means exposing your mind to true endodontic education, not merely indoctrination. The next few years will see many new concepts introduced to endodontics. Everyone must evaluate these with an open mind, not a closed one. Think through the concepts and consider the techniques. Please let us never forget that the end user (beneficiary) of all our education is the patient.

An additional area of endodontics that will continue to experience change and controversy is instrumentation. We were very pleased at "Roots" to hear another presenter (Dr. Martin Trope) express our sentiments exactly. To paraphrase Dr. Trope, "The biggest obstacle to endodontic success is the step-back preparation." We couldn't agree more. For the past two years, Real World Endo has been trying to get this point across both at lectures and in print. However, we would like to take this one step further.

We strongly believe in using a constant taper file such as a .04 or .06 taper to shape the root canal preparation. A variable taper concept, in our opinion, does not work nearly as well clinically as it does on paper. Think about it — a variable taper sequence is nothing more than a step-back preparation from the opposite end of the tooth. As a result of better manufacturing, we now have the ability, with constant taper files, to create predictable, reproducible shapes. The variable taper sequence results in a different shape each time you do a root canal. The result is a lack of reproducibility that makes obturation more challenging.

Of course, obturation by itself is another "hot topic." In fact, obturation is undergoing a serious reassessment by many academicians and manufacturers. The past 25 years saw the introduction and success of many thermoplastic techniques, but will it continue to enjoy such popularity? There are some facts well worth considering.

Previous obturation techniques were popular in the absence of serious materials science, both on the dentin side as well as the obturation material itself. But let's see where the changes in obturation are headed.

Most academicians will agree that we now have the ability to effectively open dentinal tubules. When you see SEMs showing them, it is no wonder that endodontics will see more resin, glass ionomer, and combination products come to the forefront. The most serious leakage, as we now know, is not at the seal between the luting agent and the dentin; it is the seal (or lack of) between the luting agent (cement) and the gutta percha (or similar material) that causes the most concern.

The ultimate goal in endodontics should be a true hermetic seal. Some manufacturers are already trying to achieve this through the creation of a "mono block" between the root canal wall, the sealer, and the filling material itself. We believe endodontics will see this in the very near future. The key will be in sealer development.

Before we finish, we have two questions that we want you to consider before our next column.

  • Do we obturate a root canal to get the best possible seal, or do we fill a root canal in such a way as to make it easy to retreat?
  • What shrinks more? Heated, beta-phase gutta percha upon cooling, or one of the next-generation luting agents such as resins, methacrylates, polyvinylsiloxanes, or glass ionomers upon setting?

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 at (866) 793-3636 or through