This cannot be said for all of the teeth I see.

This tooth has a lot of strikes against it:

1. Significant loss of coronal tooth structure
2. Large periapical radiolucencies on multiple roots
3. Presence of a small diameter Separated Instrument

Initial diagnosis #30:

• Previously initiated therapy
• Chronic Apical Abscess

Cases like this are unpredictable. For this reason, I typically will try to treat the areas that are accessible first. This allows me to maximize the available time to subject the instrumented canals to chemical disinfection following mechanical preparation.

Additionally, patients need to be aware that it takes as long as it takes. A patient who sighs loudly throughout the procedure and doesn’t want to be in the chair, may not be a candidate for treatment. I do not say this to be harsh, but rather to be honest and upfront. While nonsurgical or surgical treatment is relatively predictable time wise, it could take a hours to remove a separated instrument, or it may just take minutes. It may be one visit, or a few. But whether the investment is the time or the money, for some people, the investment is simply too high! This all needs to be discussed prior to starting treatment. As much as I wish it were not the case, endodontic treatment is not for everybody.

In this case, both patient and referring doctor were very much on board with taking any action necessary to retain the tooth. Once we obtained anesthesia and rubber dam isolation, we were able to move through the instrumentation phase rapidly. I was also able to isolate and remove the separated instrument from the mesiobuccal canal in relatively short order. While there were many elements that allowed me to do so, the strategic use of indirect ultrasonic energy along the length of the separated instrument was paramount in this case. While the file was visible in the coronal third, removal of coronal dentin is always the last resort for me. In this case, I was able to remove the obstruction without having to flare coronally.

Once the file was removed, we were able to complete the treatment without incident.

Some things to keep in mind:

1. All root canal systems have apical complexity, whether our instruments access this complexity or not.
2. Molar root canals present challenges that are both unknown and unseen. Ande con cuidado, no matter your level of expertise.                     
3. DESPITE WHAT SOME MANUFACTURERS ARE PROMOTING: Watch out for scouting aggressively with rotary niti files. One of the big reasons I will use hand instruments more aggressively over rotary in the initial instrumentation is the ability to control the amount of engagement of the instrument. If you bind a file on multiple surfaces for long enough, it will break. It’s like eating: it is easy to enjoy a pizza one slice at a time. If you put the whole thing in your mouth at once, not so much. Take what the tooth gives you…
4. Always watch out in mesial/mesiobuccal canals due to frequent merging. These areas are quicksand for rotary instruments if inserted too rapidly.
5. Anytime you are removing something from the canal block off the other orifices. I have seen files fly out of canals when loosened. You don’t want it flying into another part of the tooth.

“We are born of love; Love is our mother.”

-Rumi

Happy Mothers Day!

While some professionals I know are very interested in the dental literature, I have heard some dismiss it. The most common negative sentiment I have heard over the years is that it is not relevant to what is done chairside on a daily basis.

While I would like to contest that idea, the fact is, some of the literature is very difficult to tie to the things we deal with on a daily basis. However, most is certainly not all. I think the trick is to make sure that when you receive a journal, whether it is the JOE or Dentistry Today, take a few minutes to review what is in the magazine. Take what you can use and spend your energy there. If you look closely, you will probably find that there is something for everyone!

For example, much of what we know about local anesthesia in dentistry has come out of THE Ohio State University, in the Division of Endodontics. Most dental professionals use dental anesthesia in some capacity. Another such example is medical emergencies. We all treat patients with various medical conditions and being prepared to handle complications that may arise is invaluable. What is also invaluable is being able to manage these situations calmly. Over the years, I have learned that human beings can tolerate a broad range of suffering, but worrying about unknown phenomena can drive a person to the brink. In an acute situation, patients may worry, but they are relying on us to understand what is going on.

This patient presented for treatment of a maxillary second molar.

After establishing a diagnosis, treatment was completed. 

Following the postoperative radiograph, the protective eyewear the patient wore during treatment was removed and a final radiograph was taken. Upon returning to the operatory, the patient noticeably jumped in order to see me. It only took a moment to realize that her right eye was unable to migrate laterally to see me. The specific mechanism of the phenomenon is outlined in this article:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3304222/

As the article mentions, all that is required is that the patient allow time for recovery from anesthesia and the function of the affected eye would return. This is in fact what happened in our office. Now, the knowledge of this specific complication did not prevent it from happening. However, it did allow me to:

1. Rapidly diagnose the condition and reassure the patient.
2. Give the patient a time frame for recovery (that proved to be accurate-offering further reasssurance).
3. Convey to my staff and to the patient what needed to happen until the patient recovered.

If you give PSAs (and I hope you do if you treat upper molars), this may happen. Although in my 16 years of dentistry I had not seen this before, I remembered reading this article and was able to use the literature to assist me in my daily practice. With some attention to what you are reading and why, I think that you too will be able to find new information on a monthly basis that may pertain to what you do every day.

“The purpose of learning is growth, and our minds, unlike our bodies, can continue growing as we continue to live. ”

-Mortimer Adler

“Do you like surprises?”

Seems like a strange question, but it was in response to a query of whether or not we should take an additional radiograph on a patient many years ago. It also serves as a foundational value in my everyday practice. It is the reason I still strive to adequately diagnose each case preoperatively, and also why I feel so strongly about the use of multiple preoperative radiographs. But no one gets it right all the time. In this case, a young patient was referred with a necrotic front tooth. In the interest of brevity, here is the preoperative radiograph. Please note that this is the only preoperative radiograph that was taken.

Based on Clinical and Radiographic evaluation, the diagnosis is:

Necrotic pulp, Asymptomatic apical periodontitis, tooth #25.

As it so happened, I was able to inspect the internal anatomy of the tooth under the microscope, so the final radiograph wasn’t a surprise to me. However, that’s a little bit like being saved by an airbag when you weren’t wearing a seat belt. The point is this: Treatment worked out but it was only because I was able to avoid a problem that I didn’t even know was there before I got started.

In a vital tooth, the missed canal may have been more noticeable. A failure to debride the missed canal space would likely show continuous bleeding, suggesting another portal of exit. But this tooth was nonvital. Perhaps my knowledge of the literature should have suggested this as it is a common anatomical variant. But I walked in the room, saw a young anterior tooth, and got ahead of myself. Would you have done the same? Food for thought.

A tip: For those patients who are very difficult to get radiographs on, don’t be afraid to do your diagnostics off of your initial radiograph. Additional radiographs can then be taken once the patient is comfortably numb.

A second tip: Focus on a cingulum sparing access in anterior teeth. This will move you towards the incisal edge, idealizing your angle of approach to the root canal system and improving your visualization of the internal anatomy.

Also, todays digital radiography uses less radiation than ever before. I subscribe to the concept of ALARA (As Low As Reasonable Achievable), but we need adequate radiographs to do our job. My practice is no different from yours in that some patients dislike radiographs for a host of reasons. However, cutting corners fulfills no ones objectives in the end. Does anyone argue with the concept of Call Before You Dig when a construction project is starting? I think not.

And to answer the question:

“No, I don’t like surprises, not even on my birthday. And especially not in the operatory.”

See you in 2016!

While I was able to answer the question in passing, it was a question that stuck with me. A series of professional and personal responsibilities have taken up a great deal of my time over the winter and I am glad to be back sharing my experiences as an Endodontist with you. For those I don’t know personally, hopefully you will get to know me better by reading these entries.

My initial efforts in creating a blog were simply to share with the world my thoughts on a subject that is of great interest to me. In solo practice, I have an opportunity to see interesting things on a daily basis, unfortunately, other than the referring doctor and the patient, I don’t always have an opportunity to share these things with others. Also, for those who may be interested in what I do, but don’t want to ask(for whatever reason), this blog provides a look into my practice.

The patient below presented by way of a second opinion.

After suffering acute discomfort and an initial attempt at treatment, the patient was advised that the tooth should be removed and replaced with a dental implant. In addition, the patient received little information regarding an overall treatment plan specific to this tooth, the quadrant or a long term plan. Frustrated, the patient was able to secure another opinion and was referred to our practice.

While some teeth can be saved, other teeth cannot. However, I think we can all agree that each tooth should receive a fair hearing.

A couple of thoughts:

With the advent of microscopy, teeth that once could not be treated are now successfully retained. While some teeth are beyond repair, don’t be afraid to ask for another opinion! I appreciate having the opportunity to be a part of this decision making. While I enjoy saving teeth, I don’t enjoy discussing failures of teeth with patients. As such, there are times when an extraction is the best option. Some teeth have reached the end of the line.

Restorative treatment is extremely important to the long term success of endodontic treatment. Specifically, if indicated, a full coverage restoration placed in a timely manner will significantly improve the retention of the tooth. As such, any discussion of endodontic or implant treatment should include the Risks, Benefits, Alternatives(including no treatment and risks thereof) as well as the Cost. Some patients are willing and/or able to invest in endodontic and restorative treatment or implant treatment while others are not. But a failure to discuss these costs upfront benefits noone.

Finally, the bitewing radiograph is invaluable in assessing the depth of caries and the restorability of any tooth. The more you use it, the more you will like it.

I see this sort of thing with a great deal of regularity. I look forward to adding to this discussion in the next post.

I deal with the maxillary first molar more than any other tooth. Yet I am amazed daily by the anatomical variation it displays. This one though, with six canals, this one is the equivalent of an Endodontic unicorn.

I hope you enjoy looking at this case as much as I enjoyed doing it.

Happy Thanksgiving.

Approximately 10 years ago, nonsurgical root canal therapy was performed on tooth #3.

The patient presented with the following diagnosis on tooth #3: Previously treated, Acute Apical Abscess. This clinical case was characterized by a painful, localized swelling and sinus tract that appeared to be associated with the mesiobuccal root. After talking about the available options, the patient elected nonsurgical retreatment. Our discussion included the risk and benefit of apicoectomy, dental implant therapy and the prognosis of the tooth if treated through surgical or nonsurgical means. I also talked about the possible etiologies of the current condition, the most likely of which was a second, untreated mesiobuccal canal.

Years ago, I was taught that when a root canal needed to be revised, it was best to retreat all of the canals while you were already inside of the tooth. This was presented as dogma, and given the vast amount of knowledge we are taught during dental school, it was an idea that I did not challenge at the time. One of the benefits of experience is that if you continue to think critically, you have an opportunity to continue to grow. A benefit of this growth is that you may have the opportunity to take ideas you were taught and expand on them.

Surgical treatment is usually titrated, meaning when an area is detected radiographically, it is then verified upon surgical access and treatment is rendered solely upon the affected area. Apicoectomies are routinely performed on a single root, ignoring the consideration of the convenience of surgical access in treating the other roots. This is reasonable, as it would be unwise to unnecessarily damage the bone and root of a tooth unaffected by a disease process. In contrast, the aforementioned traditional thinking with regards to nonsurgical retreatment does not consider the restorative risks of retreating all of the canals arbitrarily vs. retreatment of the mesiobuccal root alone. Specifically in this case, the patient presented with acute symptoms that we can use as a reliable bellwether of the disease state. My plan was to start retreatment on the mesiobuccal root, seeking a second mesiobuccal canal. If this did not resolve the patients symptoms, we retain the option to expand the access and retreat the other two canals.

Upon access, we were able to isolate a second mesiobuccal canal, retreat both MB canals and dress both MB canals with Calcium hydroxide. In an effort to visualize the anatomy present, a cone fit was taken prior to placing the Calcium Hydroxide.

Patient presented one month later in no distress, with no signs of swelling, alveolar tendeness, sinus tract or pain to percussion. Both canals were obturated and the patient was referred back to the general dentist for access closure. Follow up contact with the patient yielded no signs of periapical or pulpal disease.

As Endodontists, we are charged with assisting patients in retaining teeth. On a day to day basis I see structural failure of teeth as the overwhelming cause of tooth loss after endodontic treatment. The wise clinican recognizes that our acts as well as our omissions may assist our patients in retaining their teeth for many years to come.

But that can only happen if we use our heads for something other than a hat rack.

Parallax: The effect whereby the position or direction of an object appears to differ when viewed from different positions, e.g., through the viewfinder and the lens of a camera.

While I first learned of this concept in grade school, in dental school I was reintroduced to the concept of parallax by way of the SLOB rule.

SLOB= Same lingual, opposite buccal.

What this means is that if the position of the patient and the sensor remain constant, you can make anatomical structures appear to move by changing the angle of the xray beam. If you are confused, don’t be. First, try the exercise as follows:

Take a look at an object nearby. Could be a doorknob, a coffee mug or something else around that size. If you close one eye (most human beings use stereoscopic vision which can complicate things-this is an endodontic blog, not opthalmology!), hold up your thumb until it blocks the object from view. Then, without moving your thumb (or the object you chose), move your head left and then right to reveal the object.

This is how the SLOB rule allows us to visualize multiple structures that may overlap in one radiographic plane by changing the angle that the beam takes to the sensor. The following case below is a good illustration of the concept.

Straight on

Beam Angled from the Mesial

Beam Angled from the Distal

The second mesiobuccal canal is palatal (or lingual for the purposes of the rule, SPOB just isn’t quite as catchy) to the first mesiobuccal canal anatomically. While each canal here appears to have been treated acceptably, sometimes this is not the case. When canal lengths or shapes have to be adjusted, you can do so by selecting different projection angles. By angling the beam from the mesial, the more lingual canal appears to move mesially. By angling the beam from the distal, the canal then seems to move distally.

Differentiating one canal from the other can also be done by using different things in each canal. I have placed gutta percha, K files, NiTi rotary files or Hedstrom files for this purpose. Unfortunately, that doesn’t warrant an entire blog post on its own. Not to mention, summer is almost over and I don’t want to waste another minute inside.

Thanks for reading!

The first thing you want to do is remember to carefully evaluate your preoperative radiograph. After doing a procedure many times, it is easy to take a cursory look at the film. I always try to review preop radiographs prior to entering the room. This allows me to start to think about what I see on the films and then once I am in the treatment room, I am able to combine my clinical impressions with the radiographs.

Sometimes you can identify the curvature and be prepared for what you are going to run into. Unfortunately, curvatures are not always apparent until you get into the case.

The next step is ensuring that you have proper access. You will note that I don’t say straight line access, as I think we have to balance the removal of tooth structure with our need to complete endodontic treatment. With that said, it is imperative that you are not fighting to get instruments into the coronal third. Whether this is mitigated through the use of an orifice opener, troughing apically or the judicious removal of tooth structure, a repeatable path into the canal is imperative. Once this is achieved, I will often use a brief sequence of crown down instrumentation using #10 and/or #15 K files. I may combine this with some initial rotary instrumentation. This is not an effort to negotiate the apex, but rather to improve access to the curvature and reduce coronal interference.

One of the techniques I have used over the years is taking an “apical impression”. I am not sure where I learned this, but once you have good access to the apical third, you can scout the area using smaller handfiles. I will often place a #10 file and instrument briefly using only a few turns of balanced force. I then will apply force apically to the file and will remove it. This gives me an idea of the degree and location of the curvature.

Some additional thoughts when instrumenting these cases:

1. Patency be established and maintained throughout.

2. Frequent irrigation and recapituation coupled with small diameter instruments, both NiTi and Stainless steel.

3. Decrease the increment that you attempt to advance down the canal. In a straight canal when working crown down, you may be able to advance a significant number of mm between instruments. When dealing with severe curves, don’t try to bite off too much at one time. Take small bites and work your way down the tooth. Patience is imperative.

4. Small diameter instruments should be your workhorses in cases like this. Their flexibility is invaluable (I know I said this in #2, I’m repeating it because it is important).

It is golf season here in Northwest Ohio. As a result, I expect to be posting a bit less in the coming months. After the winter we have had, whatever your favorite activity is, I hope you have a chance to indulge.

On a parting note, how about those Huskies!!! If one championship is good, how much better is two!

Fiber post removal is a part of what we do on a regular basis. While every tooth is different, many parts of the process are remarkably consistent. The first thing I try to do is make sure I review the preoperative radiographs carefully. These posts are often difficult to identify on radiographs as there are wide varieties available to the practicing clinician. In addition, there are many ways that they can be placed. The nice thing about identifying the fiber post preoperatively is that you are initiating treatment with a game plan in mind. Also, you are able to prepare the patients for what can be additional treatment time.

Once treatment is initiated, one of the concepts I like to use is the concept of progressive hydration. This idea is not exclusive to fiber post removal, but can be applied to many different clinical situations. It is one of the most effective ways to determine where you are in the tooth when confronted with different layers of tooth and similarly colored restorative materials. This is a higher order concept, and one that definitely requires the use of the dental operating microscope. Once the field is flooded with light and you are looking inside a tooth, you want to identify different materials. This may be restorative materials, it may be types of dentin, or something else. But often, when the tooth is dry, the various materials appear similar. Once moisture is added, this often changes, but sometimes does not. Using cotton pellets, paper points, or air, I like to reduce the moisture content slowly. As this process occurs, the different materials lose water at different rates. This allows you to differentiate between layers that earlier appeared uniform. Usually a fiber post appears as a white circle, in a composite matrix.

Once the post is identififed, I like to use a Munce bur.

This is a long shank troughing bur created by a California Endodontist, Dr. C. John Munce. John is a wonderful clinician and innovator. I really believe that you have to make this bur a part of your armamentarium and they are available here. I like to use these burs to drill directly down through the fiber post. I have found that the narrow shank helps visibility, while the stiffness allows me to establish and hold a line I can visualize as I move apically. After reaching gutta percha, I usually will use a Gates Glidden #2. This will then shred and remove remaining fragments of the fiber post.

Here are some cases that were treated that involved fiber post removal:

Fiber post removal is a complex procedure. With some experience and a plan, they can be managed predictably.

Think Spring! Or even better, Think Summer!!!

(And these are just from the past several months)

Removing things from teeth is a lot of fun. You really never know what you will find and despite your initial plan, you will often need to employ a wide range of strategies to achieve the end result. Removing these obstructions from the tooth can also be challenging. It is, however, made easier with the use of the modern technologies available to us today. Many of the things you need to remove intracanal obstructions are already in your office!

The first, is the Dental Operating Microscope. Without this tool, it is very difficult to get enough light with magnification into the field to deal with these cases. Often the micromovements of the obstruction are barely detectable, but being able to visualize it provides valuable feedback during the process.

The next is an ultrasonic device. Although I currently use P5 by Satelec, I have used the NSK Varios as well and have not been disappointed in either device.

A wide range of forceps that can be used inside of the tooth at different angles is helpful. I have acquired a number of them over the years, and usually include cotton pliers(locking and nonlocking), needle holders, and hemostats on the tray as well. You never know how the obstruction will be oriented or what the path of draw will be.

You will also need:

Composite Tips

Various assorted dispensing tips

K Files

Once you have your armamentarium in place, then you have to determine how you will put them into action. While you don’t always know which technique will ultimately remove the obstruction, it is always good to start out with a plan. A good friend of mine always says “Fail to plan, plan to fail.” I think this is sound thinking. Some of the strategies I use include:

1. Direct Ultrasonic Action

The most straightforward approach, it isn’t always my first choice, just usually. Silver points and NiTi files don’t like direct ultrasonic action, particularly when the power is too high. Water irrigation is a necessity, so it turns into true four handed dentistry under the microscope. You don’t want to see what it looks like when proper irrigation is not used.

2. Indirect Ultrasonic Action

This is a good approach when you are facing an obstruction that will not tolerate the direct application of ultrasonic energy. This is also a good approach when the obstruction can be grasped, by either forcep, braid or IRS (see below).

3. K File Braid

When you are able to bypass the obstruction in multiple locations, the instruments can be braided to grasp and remove it.

4. Swivel Tip

If you are able to fit a composite or calcium hydroxide tip over the obstruction, then you may be able to remove it.  Using composite as an adhesive allows you to use these tips to unscrew obstructions in the canal.

5. Instrument Removal System

This system is still available for removing canal obstructions. While I keep it in my office, I really only use it sparingly. I have found that is has limited versatility.

In this case, the patient had intermittent symptoms and evident bone loss secondary to endodontic treatment.

A combination of direct ultrasonic energy and braiding(with and without indirect ultrasonic energy) was used to remove these obstructions.

We were able to medicate this tooth with calcium hydroxide and subsequently obturated the case.

So far, this case has been a success. It was originally treated as an early thermafil case, and hopefully the patient will be able to retain it for many years.

Some final thoughts:

Don’t use ultrasonic energy without irrigation.

When removing separated instruments, block out other canals. Separated instruments are usually fractured under pressure and store a large amount of potential energy. When loosened this energy is released and the fragments often discharge rapidly. They can shoot out of the tooth, but they can also find their way into other canals.

Separate the removal of the obstruction into two different phases: the loosening of the obstruction and then the removal from the canal system.

Patience. You never know how long it will take and you really never know if you can remove the obstruction. Experience helps, but the process requires patience.

Next time, we’ll talk about how to deal with fiber post removal. I’m looking forward to it. But not as much as I am looking forward to this:

No matter what the groundhog says, it can’t stay winter forever!