Real World Endodontics

Sept. 1, 2004
As followers of Real World Endo know, we are strong proponents of ultrasonics in dentistry.

Products and techniques that will make your endodontic experiences better!


As followers of Real World Endo know, we are strong proponents of ultrasonics in dentistry. In fact, we believe the use of piezo electric ultrasonics is the most under-utilized technology in modern endodontics. However, we expect this to change in the very near future.

We prefer piezo electric ultrasonics, as compared to earlier magnostrictive units, for two reasons - piezo electric technology offers more “cycles” per second (40,000 CPS versus 24,000 CPS) and the tips work in a linear, back-and-forth “piston-like” effect. This motion is ideal for endodontics. This is particularly evident when “troughing” for hidden canals. A magnostrictive unit, on the other hand, creates more of a figure-eight (elliptical) motion. This is not as ideal for surgical or nonsurgical endodontic use.

Many dentists continue to have the impression that ultrasonic use in endodontics only has a surgical application. This is not true. An estimated 90 percent of all ultrasonic use is in nonsurgical endodontics. In our opinion, if you are serious about doing quality endodontics, you need to have a piezo electric ultrasonic.

Once we grasp the notion of ultrasonics in endodontics, the next area of focus is the unit itself. This is where things change significantly. As part of our “EndoSequence System,” Real World Endo is proud to introduce a new ultrasonic - the “Varios 350.” This unit is manufactured by NSK and is distributed in North America by Brasseler USA.

The “Varios 350” is a piezo electric ultrasonic that fits in the palm of your hand! Yes, you have read the previous statement correctly. The 350 is the smallest unit on the market and it fits easily on any bracket table. It is so small that you can even place Velcro straps around it and place it anywhere you wish. In fact, this unit, in combination with a portable handpiece, makes hygiene and endodontics truly portable. Additionally, the design of the unit allows an easy wipe down (disinfection).

While the size alone distinguishes this unit from all others, another feature gives the unit a new dimension. The “Varios 350” comes with a fibreoptic built into the handpiece. The fibreoptic is protected and is precisely directed to the field of treatment. This is unlike any other fibreoptic - the light is completely circumferential and surrounds the tip. Why do we believe this is a quantum leap forward in ultrasonics? Let’s think for a moment about the benefits of fibreoptics.

The primary benefit of having a fibreoptic built into an ultrasonic is enhanced vision. Not only will all clinicians be able to see better, but the fibreoptic actually creates a “wand of diagnostic ability” for both the hygienist and the dentist. By employing trans illumination (shine the light through the tooth at the CEJ), we can now readily diagnose cracks, fractures, and even calcified canals. Additionally, think how great a fibreoptic-based ultrasonic is to see subgingival calculus! For those clinicians performing surgical procedures (endodontic or periodontal), the “Varios 350” will specifically illuminate your surgical site, making your life a lot easier.

The handpiece itself is small, light, and ergonomically designed for excellence. A thin handpiece, when combined with a fibreoptic and the use of ultrasonic tips, allows the practitioner more visual access to the procedure. In endodontics, we have access to the tooth and straight-line access to the canals, but we also need visual access to the procedure. Take a look at the “Varios 350” and pick up the handpiece. Take it for a test drive on a tooth. You will be stunned that such a small ultrasonic can be so powerful. We think you’ll like it!

Another critical factor in the use of piezo electric ultrasonics is the selection of tips. The “Varios 350” comes with a huge assortment of tips. Tips are available for endodontic, periodontal, and even general procedures. Additionally, Real World Endo is currently designing multiple new endodontic tips for both surgical and nonsurgical use. To further facilitate the use of this unit, we have created combination packs that include both endodontic (three) and periodontal tips (three). An ultrasonic tip caddy (UTC) helps keep things neat and organized in the treatment room.

Having just discussed the merits of what we think is an exciting unit (Varios 350), let’s review some of the uses of piezo electric ultrasonics in endodontics.

Finding hidden canals

In addition to length control, the biggest challenge facing the general practitioner is finding the canals. Endodontic cases are becoming increasingly difficult, particularly those cases where the orifice has become occluded by secondary dentin. You can’t perform root canal therapy unless you find the orifice. Piezo electric ultrasonics are excellent for removing the secondary dentin that often slopes off the mesial wall. This is what blocks the MB-2 canal in maxillary molars. It is particularly in these maxillary molar cases, when looking for the MB-2, that the “Varios 350” shines! A good tip to remember when searching for hidden canals is that secondary dentin is generally whitish or opaque, while the floor of the chamber is darker and more gray-like in composition. The fibreoptic can really help the clinician in these cases by making this an obvious distinction.

Piezo electric ultrasonics also perform particularly well when breaking through the calcification that covers the canal orifice. A troughing tip is a good choice for this task. As a result of the “graying of America,” along with the increased popularity of posterior resins, we are seeing more coronal calcification. If you treat geriatric patients, the solution is obvious. You need to have a piezo electric ultrasonic and you need to have visual access to the procedure. Take advantage of this new dimension.

Increased efficacy of the irrigation agent

Real World Endo firmly believes in “precision-based endodontics.” We also embrace the concept that “instruments shape, irrigants clean.” However, how can we make our irrigation more effective? By placing an ultrasonic tip into the bleach that is in the chamber, we can enhance the cleaning efficacy of our irrigation agent. Why? An ultrasonic creates both cavitation and acoustic streaming. The cavitation, which is like the action created with a boat propeller, is minimal and restricted to the tip. However, the acoustic streaming effect is significant. The only way that you can effectively clean webs and fins is through movement of your irrigation agent. One cannot mechanically clean these areas. Ultrasonics are a great help in cleaning these difficult anatomical areas. Multiple research in the early 1980s showed that the cleanest canals are those that follow instrumentation with a brief period of ultrasonic cleaning, and current endodontic research confirms the earlier studies. For example, in the October 2003 Journal of Endodontics, R. Sabins et al concluded that, “Ultrasonic passive irrigation produced significantly cleaner canals than passive sonic irrigation.”

The technique itself is quite simple. Choose a basic spreader or troughing tip, turn off the water, and place the tip into the irrigation agent. You will notice lots of effervescence (bubbles). After about 30 seconds, you may have evaporated the solution. If this happens, simply replenish the solution and repeat for another 30 seconds. With this procedure, we are generating extensive streaming of the irrigation agent. The net result is a cleaner root canal system. This is particularly beneficial in cleaning large fins (such as C-shape canals) that hold excessive amounts of tissue. Our recommended time for acoustic streaming is 60 seconds.

Removing posts and cores

As previously mentioned, endodontic cases are becoming increasingly difficult. Many of these cases will involve removal of a post. There are many expensive gadgets available that supposedly remove posts. Unfortunately, some don’t work as well as advertised. Furthermore, some have problems with freeway space in the posterior part of the mouth. In our opinion, post extractors should only be used as a last resort. We prefer to remove posts with an ultrasonic. Piezo electric ultrasonics, in particular, are a tremendous help in post removal. Here are some tips you should know.

When removing a post, it is critical to break the seal between the post and the tooth structure. This can be accomplished initially through the use of a surgical length 1/4 round bur. This is technique-sensitive, so be careful to go along the long axis of the root. Once you have trephinated around the post, you can place an ultrasonic tip into the trough (a basic spreader tip will do fine). This will further break the cement or resin and you will soon notice motion in the post. An alternative way to break the seal is to initially use a spreader or troughing tip. Sometimes you can place a spreader tip against the post itself. This works well if the seal has been broken. Don’t rush when removing posts. Take your time and don’t panic. The post will come out.

We also strongly recommend using spreader tips with water spray. If you run a spreader tip dry, bad things happen. First, the handpiece on some units becomes very hot and the ultrasonic tip gets overheated. Secondly, the post becomes heated and this heat can eventually be transferred to the periodontal ligament. Lastly, when using an ultrasonic without water spray, you will have an increased smell of burning dentin. Nice, huh? These dilemmas can be avoided through the use of an ultrasonic tip with a water port. If you want to use the ultrasonic “dry” for a few seconds, simply turn off the water. More importantly, the water is there when you need it.

Furthermore, it is obvious that a fibreoptic-based ultrasonic will greatly enhance the ability of a clinician to remove a post. Enhanced visual access will ensure a more conservative removal of the post. If too much tooth structure is destroyed during removal of a post, it will complicate the restorative aspect of the tooth and will most likely decrease the overall prognosis.

Removing separated instruments

Sadly, it is a fact of life that some endodontic instruments can break. Fortunately, piezo electric ultrasonics are excellent for removing separated instruments. However, you must be aware of the importance of the location of the separated file. If a rotary file is separated past the canal curvature, this will be extremely difficult to remove. Don’t fall prey to those “experts” who cavalierly say, “I just pull over my microscope and remove it.” These are difficult cases. On the other hand, broken instruments in the coronal half of the canal can be removed in a relatively straightforward manner. However, be honest to yourself. If you do not have the experience, or necessary magnification, you may want to refer this case.

When removing a broken instrument in the coronal third, a thin spreader tip will work nicely. Most ultrasonic companies have tips specifically designed to remove broken instruments. Take the tip into the canal and work it in a counter-clockwise motion around the broken fragment. This will generally dislodge the broken instrument. However, please note that referring to an experienced clinician with the use of a microscope is the best choice for removing instruments separated in the middle or apical third of a canal.

Piezo electric ultrasonics have a host of other indications. For example, placing a vibratory tip against the buccal surface can loosen poorly fitted crowns. Another indication is the condensation of certain restorative materials. However, the most extensive use of these units, besides endodontics, is in hygiene and periodontics. A fibreoptic-based ultrasonic makes great sense to any periodontist or hygienist. It is all about enhanced visual access and better treatment for the patient.

We have attempted in this brief article to convey our enthusiasm for the new “Varios 350” ultrasonic unit. It is the combination of both a miniature size and powerful fibreoptic source that truly makes this a next generation unit. It introduces the clinician to an entirely new dimension in ultrasonic use.

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

Dr. James Pride passes away

Dentistry mourns the passing of one of its great leaders, James R. Pride, DDS, who died on August 11 after a long bout with cancer. He was 68 years old. As a visionary thinker, innovator, and charismatic speaker, Dr. Pride leaves an indelible mark on his profession and on those who knew him. He worked as a clinical dentist, assistant dean of the University of the Pacific School of Dentistry, and founder of Pride Institute, the practice management company where thousands of dentists have learned to apply his innovative teachings to achieve practice success. “We mourn the passing of our much-loved founder,” said Amy Morgan, CEO of Pride Institute, “while we maintain his legacy and celebrate his life through our continued growth and success.”

During his distinguished career, Dr. Pride introduced many innovations that have now become standard practices in dentistry, such as dual-entry operatories, 10-minute appointment scheduling, statistical benchmarks to quantitatively analyze the dental practice, and, in general, an unprecedented scientific approach to leadership and management which revolutionized every dental office system. He led the vanguard to prepare dentists financially for retirement and also created original concepts and agreements for practice transitions, which have aided dentists in making pivotal changes at the crossroads of their lives. His teachings resulted in hundreds of dentists and their families expressing their gratitude to him for enhancing their lives, both personally and professionally, and transforming their future.