Bite Point

Frisbees

I would like to talk about a teacher. There are many I could riff on. I will choose Dr. Byron Kern because I just saw in the Pennsylvania Dental Journal that he passed away recently. He was 94.

Dr. Kern was one of those many practicing dentists who (as I have done) gave of his time to teach part-time in a dental school or residency, for little or no compensation. He had the knowledge and patience to teach full dentures exclusively. This is a very subjective and demanding art; it was expecially so in the days before implant support made firm anchorage possible.Dr. Kern taught me that humor was an excellent addition to all the science, art, and human relations we must know so much about in order to treat our patients successfully.

When I was delivering my very first completed full denture to a patient, it fit ideally. This had a lot more to do with Dr. Kern's guidance than with my skills at that point. He had taken me to the end result with all the thrashing at the beginning, which as many of you know is the best way to go on any project. My patient was pleased, I was pleased, and Dr. Kern said, "It's a Frisbee!" This, from a man who was hitting seventy! I was tickled denture-base pink with the idea of calling dental restorations that fit ideally with no adjustment "Frisbees."

To this day, in our office, Frisbee is the word we use for things that fit without adjustment.

After that time, a new patient was scheduled with me who had an unusual request. She was an Eastern European woman who wanted a gold-based denture. This is a denture with a cast gold alloy internal portion that fits against the gum tissues. Up from that comes the pink acrylic and then the artificial teeth. They are very accurate, these gold-based dentures, just rare to make because of the added expense. Mind you, the gold is to be very thin, and it's an alloy, but still: expensive.

So we got the base back from the lab as a first step and someone there had lost their mind. The gold base we recieved was massive. It must have contained an entire one of those ingots that you always saw referred to in 60's sitcoms and Bugs Bunny cartoons along with a reference to Fort Knox, an entity that many young people today are probably completely unaware of. In any event, this denture base could have been a buttressing member for the Market Street El, it was so big and heavy.

I showed it to Dr. Kern with marked trepidation. He took one look at it and then uttered those immortal words: "Rick, if we made her a denture with this base and she went swimming, she'd sink and drown."

And with that hilarious comment we sent it back and had it remade- too small the second time. Finally, on the third try, the lab techs solved this gnarly variation on The Goldilocks Problem (dentures and porridge!) and we were off to make the best-fitting denture made at Penn Dental that year. Yes, I am convinced of it.

Dr. Byron Kern was a gentleman and a gentle man. He knew the science and the art that forms the foundation of our field, and understood the art of dealing with human beings in a respectful and goal-oriented manner. He also knew the value of laughter- how it healed, how it helped get a patient through a complex course of treatment. I thank Dr. Kern for teaching me the value of striving to create something that fits exceptionally well. I thank him for all the things he taught me. 

And for the Frisbees.

Memorial Day Post: Captain Ben L. Salomon

Thank you to all who have served, from our Revolution to the present day. And particular thanks this day to Captain Ben L. Salomon, September 1, 1914 – July 7, 1944, who posthumously won the Congressional Medal of Honor "For conspicuous gallantry and intrepidity at the risk of his life above and beyond the call of duty." He saved more than 30 wounded American's lives at the cost of his own. To my knowledge, he is the only dentist ever to have received our country's highest military honor.

http://en.wikipedia.org/wiki/Ben_L._Salomon

Composite Resin Longevity

There are still rumblings in some quarters about how composite resin restorations don't work very well, don't last very long, and get all kinds of recurrent cavities underneath them. 

First of all, it's dental amalgam (which dates from at least 1833 in the U.S.) which fails from the inside out. Dang, the situations that we find under apparently intact amalgams are like something out of a Stephen King novel, sometimes. Composite resins usually have the excellent feature that if they fail, it's from the outside in. They give us notice.

More on dental amalgam here, if interested:

http://rickwilsondmd.typepad.com/rick_wilson_dmds_blog/2009/11/amalgam-politicians-and-all-the-pink-trees.html

Composite resins can be extraordinarily successful if the enamel and dentin are treated properly. For back teeth, this requires the use of self-etching primers, careful placement of flowable composites as first layers that intimately adapt to the dentin, placing increments of the main composite so as not to let curing stresses pull the materials away from the surrounding tooth structure, and finally a great wedging and contouring system.

More here:

http://rickwilsondmd.typepad.com/rick_wilson_dmds_blog/2010/11/enamel-bonding-dentin-bonding.html

Let's look at a practical example.

These three restorations were placed five years ago, in 2007. For various reasons my patient has not elected to restore the center tooth with a crown, which, speaking ideally, is indicated. The support pins show at the surface intentionally, because the material is less likely to break that way, at least according to one study. And yes I saw the bubbles as I lined up the shot; this one time, I left them, because they looked kinda fun.

Five years. No recurrent decay, no symptoms, no root canal necessary yet, reasonable wear of the restoration surface. And yes, a sample size of one is merely anecdotal evidence. So I read the literature and also watch hundreds, perhaps thousands, of these restorations year after year in my practice and can never blame problems directly on the materials themselves. It's either me, or the patient if they have poor oral hygiene and excessive sugar intake in their diet. Hey, man, a destructive plaque will destroy anything. Even then, we see the cavities beyond the composite resin restoration, on the root surface. 

The materials we used were:

Bonding agent: SE Bond

Flowable composite Resin: Flow-It

Composite Resin: Heliomolar

Matrix: Bitine Ring

This system works because the best self-etching primers work. I'd only use two brands as of 2012: SE Bond from Kuraray and Prelude SE from Danville Engineering. These two products minimize problems including transudation issues, which means water moving up from the dentin in the tooth and pushing bubbles into the resin-tooth interface, weakening the bond. This is kept to an absolute minimum with these two products.

Thus, so far as I can tell, in practical terms, this restoration is as fine at the five year point as it was when I placed it.

 

Real Versus Cosmetic

Question: What's the difference between a "cosmetic" dentist and a real dentist?

A cosmetic dentist places eight veneers and they all look natural. A real dentist sometimes places one veneer, when strongly indicated- and it looks natural.

Bone Grafts In Dentistry: The Bone Sets The Tone

We often need to regain bone in the jaws, bone that has been lost for all kinds of reasons. The main indications for bone grafting are site preparation for dental implants, and periodontal surgery, to regenerate the bone support that can be lost by periodontal disease.

The idea of "grafting" bone is easily misunderstood. Although we can add large volumes of grafting materials, it is still the patient's own body that does the healing and rebuilding. Our regenerative materials mostly provide a scaffolding into which the body sends blood vessels, immune cells and eventually the cells called osteoblasts and osteoclasts that can form new bone. 

What, then, are these substances that we use to provide this scaffolding? We'll get into definitions in a minute, but first let's review the most common sources that are used. The current commercially available sources for dental bone grafts include: human, bovine (cow), porcine (pig), equine (horse), and totally mineral (rock).

Gosh, the incredible variety of origin of these materials, and thoughts of how different cultures and religious traditions might view them, reminds me of the old joke. You know- there's a Jewish dentist, a Muslim dentist, a Hindu dentist and a Lutheran rodeo star and...oh, never mind!

When teeth are lost, the bone is often damaged beforehand, as the tooth slowly fails. It also pretty much flies away after the extraction. This is especially so on the outer, or buccal, bone. The buccal plate is very thin in humans and does not have much ability to repair itself; see:

http://rickwilsondmd.typepad.com/rick_wilson_dmds_blog/2010/08/bundle-bone-and-dental-recession.html

A fine example of increasing the amount of bone in preparation for placing a dental implant is to be found in moi! I never developed my two upper 2nd premolars. My primary teeth hung in there for a long time but were finally getting weak, and to prevent breakdown of bone in the area that could affect the adjacent healthy teeth, I had my friend Thomas Kohler, periodontist extraordinaire, extract them in 2010. The thing was, there was not anywhere near enough bone height or volume for implant placement. I'll just show one side since right and left were both very similar. I've marked a thin black line along the boundaries of my bone, before and after the procedure. To the south is gum tissue, and to the north is my sinus. Dr. Kohler skillfully raised my sinus with the bone graft in order to create an acceptable implant site. The graft material, in this case highly inert, processed bone from a human source, was turned over into my own bone by my body's metabolism in about four months. Let's have a look at the X-rays:

What a difference! Oh, ok, and since you asked, here's the implant in place:

The funny-looking part between my teeth is just the impression coping, not the final crown or any sort of device that picks up enemy radio transmissions. It is used to register the precise position of the implant and my teeth and gums so that the lab can make me my new premolars.

Clarification of these choices in bone graft materials is my main goal with this post. Patients often want to know details about what materials are being used in any medical procedure.

We first need to define the general categories of bone graft materials. The first sentences are all from dictionary.com:

Autograft: A tissue or an organ grafted into a new position in or on the body of the same individual. So, for our purposes here, Own Grown Bone.

Allograft: A tissue or organ obtained from one member of a species and grafted to a genetically dissimilar member of the same species. In other words, bone from someone else, but still from a human. (Which means politicians cannot be donors under any circumstances.)

Zenograft: A tissue or organ obtained from a donor of a different species from the recipient. That's the bovine/porcine/equine vibe.

Synthetic or Artificial Bone can be made from purely mineral sources. Put simply, synthetic bone grafts don't come from a human, a cow, a pig or a horse- they come from a rock.

We can sometimes get autograft from other parts of the mouth during periodontal or implant surgery, but it's often difficult to get very much of it. Own Grown Bone can also be obtained from the iliac crest of the hip, but of course this involves a separate surgery and the skills of someone in addition to the dentist. (Our training includes lips, but not hips.) Also, the street cred on autografts is that they are preferable because the bone is "live" in some way, but the research clearly shows that whatever we place into an extraction socket is a dead mass until the body sends new blood vessels in there and starts rebuilding. So there is really not an advantage in that respect.

Allografts are readily available for purchase and the treatment of bone materials from human sources is rigorous, making them extraordinarily safe. The steps include donor screening, serum testing, delipidization with acetone and ultrasound, gamma irradiation, and hydrogen peroxide oxidation treatment. In any way of measuring risk, going to a restaurant is more dangerous than having these materials placed in an oral surgical site.

Xenografts are also readily available. I'm not aware of definitive research on all products, but studies in Sweden and the U.S. have shown that not all of the xenograft particles "turn over" (or "resorb") so that one's own bone replaces them completely. In other words, and in particular with bovine bone, each graft particle remains like a sort of mini-implant, an island of mineral bone matrix within the host's newly formed bone. This is not at all a problem, in fact these sites can have excellent form and function; it's just different than when all the bone eventually becomes the host's, as in autografts and allografts.

Synthetic bone, as I mentioned above, is derived from mineral sources. The trick is to make them properly porous so that blood vessels can invade and bone matabolism can start within them. This porosity is of course provided naturally in the other sources we've talked about. These products claim to be completely resorbable.

As a final exercise for patients who are considering oral surgery involving bone graft materials, let's run down some specific brands and product with which I am familiar. There are certainly others, and I do not mean to endorse any particular product, nor am I paid or otherwise compensated by any commercial interests everrr, although that's probably a sweet deal if you can get it.

Ok, here we go:

Puros. This is an allograft. It is manufactured by Zimmer:

http://www.zimmer.com/en-US/index.jspx

This is also the one in me. Well, it was in me, now it's all my own bone, the turnover is essentially complete. It is now available in particulate form or particles in a paste form, so it is widely adaptable to various surgical situations. Dr. Kohler and I chose it together for my case for reasons of performance. Meaning, in our hands, with our skill sets and instrumentation, we have noted the best results from Puros over time. For now. This is where the experience of the individual practitioner intersects with the body of controlled scientific research that exists at any given time, and the best decisions are made when both realms are considered.

IngeniOs. Also a Zimmer product, this is synthetic. Specifically, it is a resorbable, silicated beta-tricalcium phosphate, for the chemists in the audience. The key thing is that it is porous and it does turn over into Own Grown Bone eventually. 

Equimatrix. This is an Osteohealth product.

http://www.osteohealth.com/

This is a new product and, as the name indicates, is equine. They seem to have discontinued Bio-Oss, which was bovine, in favor of this new graft material.

I hope that this helps to make sense out of these choices for patients. There are further complexities like the choice between particles versus pastes versus block grafts for larger reconstructions. There are also formulations that add various bone growth factors in attempts to speed up bone growth, or make it more thorough.

The choice of bone graft materials is a highly individual one and is best made between the dentist and patient working together. Autografts are very appealing if enough bone can be obtained from the mouth, but few patients would want a second surgery on their hip unless it was vital to the case outcome. Allografts are quite safe, yet some patients have reservations about them in spite of all the processing that they undergo, or even because of what some describe as "the yuck factor" when they admit they have no real reservations about them. Bone grafts from animal sources may be unacceptable for some patients due to religious reasons. These are all valid concerns and I am happy to have completely synthetic sources as well, although as I stated when discussing my own case, I understand the safety quite well and went with an allograft for reasons of performance. I wanted lots of strong, dense bone, and I got it. Thanks, Dr. Thomas Kohler and all the little people, the osteoblasts and osteoclasts, who helped me have upper second premolars for the first time in my life!

So cute!!

The Indian Tale of the Blind Men and the Elephant- and the Dental X-Ray

I was very young when I first heard of the ancient tale from India of the blind men and the elephant. This tale spread far and wide, but the Indian version is probably the original and is definitely the most succinct.

From the Wikipedia entry, 

http://en.wikipedia.org/wiki/Blind_men_and_an_elephant

Ramakrishna Paramahamsa used this parable to discourage dogmatism: "A number of blind men came to an elephant. Somebody told them that it was an elephant. The blind men asked, ‘What is the elephant like?’ and they began to touch its body. One of them said: 'It is like a pillar.' This blind man had only touched its leg. Another man said, ‘The elephant is like a husking basket.’ This person had only touched its ears. Similarly, he who touched its trunk or its belly talked of it differently. In the same way, he who has seen the Lord in a particular way limits the Lord to that alone and thinks that He is nothing else."

I shall refrain from any discussion of how this applies to modern American politics and the religious sphere. But to dentistry, it also has tremendous relevance.

For my entire career I've been intrigued by how 2-dimensional X-ray images represent, and misrepresent, 3-dimensional objects. I've posted before on how the level of bone or a small chip in enamel can be superimposed over the rest of the tooth in such a way that it looks like a cavity. Well, we took some X-rays recently that show a large cavity with tremendous variation in how it actually looks.

As we look at the images, recognize that the dark curvy lines inside the teeth are the outlines of the root canal. The white lines are an existing root canal treatment and post. The other white things are metal restorations.

In this first image, focusing on the tooth with the question mark, we see a hint of darker gray under the light filling, which could be a cavity:

However a dentist could perhaps be excused for thinking nothing of this shady shading and, if no open decay was visible to the eye (or touchable to those little sharp silver things that we're always poking around with), leaving this tooth be. Because, you see, the line of the dense bone throws a shadow right along this part of the tooth and it's supposed to look a little darker there. Same picture, with a line drawn along the bone crest:

Lighter below, darker above. Definitely a confusing area for interpretation.

Yet a Full Mouth Series of radiographs picks up different views of the same tooth. Much like those chaps investigating the elephant, we start to see different aspects of the same thing:

And for the win:

The bone may set the tone, but that's decay!

So multiple radiographic views of teeth are often vitally important in diagnosis. This is even more true when we get into diagnosing periodontal disease, endodontic lesions (infections in root canals), cysts and the like. The new 3-D scanners are a great advancement in this regard. They do not yet have the resolution to detect small cavities, but in short order they probably will. Until then, it's sometimes a challenge to know the tusk from the trunk.

eCharts: We Are Now Paperless

Today, 3/5/2012, was Der Tag. "The Day." The moment when we transitioned from paper charts to eCharts.

Everyone survived!

We've been working with digital images for about five years now. We've been emailing letters to specialists and recieving theirs back in turn via electronic means. We've been treatment planning in our Dentrix software for quite some time as well. So this wasn't all new to us. Still, it took a leap of faith to change in this way. Now that the day is done it feels pretty good.

There are major advantages to this:

Faster! Because we work from pre-written Templates that we modify to fit the specific situation as needed.

Neater! Because no one has to read my meshuggenah handwriting.

More thorough! Because we don't have to worry about space concerns. The real world is often one of scarcity. We didn't want to waste paper because we'd have to order more. The digital world is one of abundance. We still won't waste space. But if we wish to write more- we'll write more. It entails no cost.

Environmentally friendly! We use a bit of power to run our computers, of course. But we turn them off at the end of the day, except for our server. And we no longer consume: paper, ink, the energy and chemicals required to make paper and ink, the energy and chemicals required to transport paper and ink, plastic in the casings of pens, etcetera, etcetera, etcetera.

Der Tag went well.

 

2012 Super Bowl XLVI Gatorade Shower

Here it be:

 

What to say about Gatorade this year, my third of mulling over the Super Bowl Gatorade Shower?

I was stuck until I realized I had already written it.

I'm posting an excerpt from something I'm writing. The two characters are brewers. Aloysius St. James Spottisworth-Gack is leader of a craft brewery, Gack&Bacon Ltd, that has been in continuous existence in England since the reign of Queen Elizabeth I.  It's the 60's, and Alabaster Prufrock Slore is the CEO of a very corporate brewery that's a lot bigger than Gack&Bacon Ltd. And a lot less interesting...

It comes to pass that they duke it out on Panorama, an uber-cool British news and commentary show (still on) that in those days was hosted by the British Walter Cronkite, a brilliant chap called Richard Dimbleby.

When you next see Gatorade's marketing, which makes water, sugar and some salts out to be The Fountain of Youth, come back and read this exchange between the corporate and the visceral:

Gack said, "In addition, with advertising, you have the issue of transparency.”

Dimbleby, intrigued: “Meaning what, precisely, Mr. Gack?”

“Well, most adverts present a, shall we say, idealized version of the product or service that they’re attempting to make us aware of.”

Slore, snippily: “That’s just putting one’s best foot forward.”

“Not when it crosses the line into being deceptive.  Which so many ads do.  They promise glitz and glamour where the product is only dross.  Romance when the customer is only going to be let down by the banal.  Powerful experience where there is really no experience at all, only a commodity.”

**********

More on that here:

http://rickwilsondmd.typepad.com/the_man_who_wore_mismatch/

**********

I do have my own ad in mind, by the way.

"Gatorade. Is it in you?"
"Hmmm let's see. Calories... Cavities...Cost... Nah. I'll have water and a banana instead."

"NOW Can I have me some chewin' room?"

From the movie that remains, to this day, my favorite comedy, 1965's The Great Race:

Larry Storch's character, Texas Jack, says to Tony Curtis' always-spotless-white The Great Leslie: "Now can ah have me some fahh-tin' room?" in a schtick that repeats several times; sorry, tahmes, each more hilarious than the last. Here's the clip:

http://www.youtube.com/watch?v=Q6Pl71RpFRs&feature=results_main&playnext=1&list=PL1372D1D48A184993

Well, it is hilarious to a guy like me, who appreciates the slower, kindlier humor of that bygone era to today's often highly mean-spirited stuff. So many things in our culture have improved, but I submit that film is not one of them.

And so that Texas Jack clip is what I think of when I see prior dental treatments that fail partly because there wasn't enough "fahh-tin' room", or enough space for the restorative materials that we so often place in and on teeth in order to keep them going after they've been harmed by decay, fractures or just overall wear.

There are many types of dental crowns. The workhorse of the 20th and early 21st Century is the porcelain fused to metal, or PFM. This type of crown has a layer of semi-precious or non-precious metal, cast or milled, covering the tooth. The functional shape and esthetic look is then completed by porcelain layered on top and around the sides. Nine out of ten dentists, and eleven out of ten dental educators, assert that the materials involved in a PFM need to be at least 2 mm thick on the biting surface of the tooth.

Another way of looking at this is, we need to remove enough old filling and tooth to provide 2 mm of clearance between the opposing teeth and the one we're working so hard to restore.

Here is a pair of images of an old crown that I removed and sectioned:

 

The striking thing to note is that the porcelain on top of the tooth, on the biting surface, is very thin. Yes, it wore a bit over the years that this crown was in service. But porcelain wears slower than opposing teeth, when it is properly placed onto the metal. This crown started out on an underprepared tooth. It wasn't given enough fahh-tin' room between the top of the crown prep and the opposing teeth. Thus, the porcelain was very thin. The deeper layers of porcelain are opaquers and coarse layers that are not as effecive as the final ones at holding up to the rigors of chewing day after day. Thus, they wear away quickly and what was at first a thin layer becomes an uber-thin layer that tends to fracture.

It is said that the rate of porcelain fracture in new crowns done in America at this point is about 5% over the first five years. This includes every kind of fracture, from big ones that render the crown unserviceable and in need of replacement down to minor fractures that can simply be polished away. Still, everything we can do in dentistry to minimize treatment failures is important, and ensuring adequate reduction of our crown preps is vital.

Patients- if you ever have a "PFM" crown done and the biting surface shows metal or looks very odd  compared to the beauty of the rest of your crown; say, opaque and flat-looking, rather like a lawn ornament (I'm thinking plastic pink flamingo here); then there was probably an issue with the clearance between the treated tooth and the ones that oppose it. This truly should be corrected before your new crown is cemented into place, only to face a high likelihood of breaking in a short time.

Returning to important matters, the scene in the above Youtube clip must certainly be the greatest bar fight ever put on film. Barstools fly. Bottles are smashed. When the staircases come down, it's just magnificent. And there's that quirky exchange between Lily Ole and The Great Leslie early in the clip:

Lily: "Honey, your smile is downright painful!"

Leslie: "Thank you. Are you a native of Boracho?"

Indignant Lily: "I ain't no native, I was born here!"

But the pie fight... oh yes, the pie fight. Definitely, at 2,357 pies, the grandest pie fight ever on film.

http://www.youtube.com/watch?v=-0BOOgW7rHE

You will not regret watching it!

"Y-o-u  w-o-u-l-d-n-t  d-a-r-e!"

Root Canal Therapy: Take Two! Guest Post by Neha Shah, D.M.D.

Superb endodontist (and awesome human being) Neha Shah DMD writes our latest guest post and explains a pervasive mystery in dental treatment:

Many people are surprised when they hear that they need a root canal on a tooth that has already been previously root canal treated. Wasn't the entire purpose of doing the root canal to not to ever feel pain again in the tooth? Commonly I hear from patients, “All the nerves are out, so how come this tooth is hurting?” The most common misconception from patients is that when a tooth has had root canal treatment, it is as if the procedure has created a force around it so strong that not even kryptonite can penetrate it. However, this is far from reality.

When a tooth has been treated for a root canal, it is in essence "rendered dead". A tooth that has had root canal therapy is essentially void of the living pulp tissue at the core of the tooth and therefore not able to respond to temperature stimulation. So the tooth is not able to tell you if something is hot or cold. However, it is still able to perform other functions of a mature, vital tooth because it still has the basic structures of a natural tooth namely enamel, dentin and cementum. This is what renders it susceptible to all of the threats that a vital healthy tooth is susceptible to. In fact, some may argue that a root canal treated tooth is slightly more vulnerable than a healthy, vital tooth. This means a tooth that has been treated for a root
canal is susceptible to decay (cavity), fracture, and infection just like any other tooth in the mouth. So it is imperative that a root canal treated tooth is properly cared for and protected.

One of the biggest threats to our teeth is BACTERIA. Our teeth are constantly bathed in saliva that have bacteria. These bacteria which are naturally present in our oral cavity are opportunists and when the environment is ripe will attack the basic structures of the tooth. So at every opportunity, at every level from performing the root canal, to sealing the root canal, to sealing the tooth, this basic goal of keeping the bacteria out is practiced by dental health provider and encouraged to patient.

So what is causing that root canal treated tooth to hurt? Infection and Inflammation. For every infection there is associated symptomatic (painful) or asymptomatic (no pain) inflammation. The primary reason why root canal needs to be redone is for what we term "coronal leakage" ("coronal" meaning "crown"). What this essentially means is that bacteria have penetrated through and into a previously disinfected root canal system. Other less common factors that lead to retreatment is a previously untreated canal, undetected root fracture, or persistent infections within the root canal system due to complex anatomy or extraradicular infections. Regardless, the common thread that runs through these causes of failures is again bacteria, "bugs", or microorganisms.

In a nutshell, the etiology is bacteria and the treatment is disinfection. This is precisely the primary goal of retreatment therapy. During retreatment any existing restorations or posts leading to the root canal system have to be disassembled. The root filling material has to be removed and the entire root canal system has to be disinfected. Once the disinfection process has been completed which usually is completed in two or more visits, new root filling material is then placed and once again an opportunity has been set to seal the tooth properly and restore it to full function. In essence, retreatment is like giving the tooth 2nd life. In some
ways you can use the analogy of the life lines from “Who Want’s to be a Millionaire?” #1 life line for a tooth is root canal therapy. #2 life line is your endodontist when (s)he performs retreatment procedure due to reinfection of the initial root canal therapy and your last life line is your endodontist when (s)he performs an apicoectomy on a tooth that has already had root canal therapy more than once. Your million dollar is when you save your self of the aggravation of extracting the tooth and finding a way to replace it with a prosthesis.

To illustrate, here is a case that has failed for many of the reasons mentioned above:

*Coronal leakage
*Missed canal
*Separated files
*Persistent infection due to anatomy
*Inadequate initial debridement

 

 

Once the etiologies were identified, all of them needed to be addressed to set the stage for success.

For the above case, the tooth’s prior root canal had to be disassembled through a permanent crown. Goal of the retreatment for this case was to remove post, remove separated files, locate additional canal, remove existing root filling and fully debride and disinfect root canal system and medicate to create an environment for healing. The last two x-rays show the finished treatment.

You may realize that the tooth behind the one that was treated is in a similar predicament. It too will require retreatment for long term success.

Root canal therapy is a highly predictable, highly successful procedure when the tooth is treated and restored properly. Like any medical/dental procedure, the responsibility of performing the procedure properly lies in the hands of the health care provider but the care and maintenance after the procedure is shared by the patient and the provider. Remember, if at first you don’t succeed, try, try again.

(Dr. Shah practices at TEC Endodontics: http://www.tecendo.com/)