The Endo Fix

Categories

© 2017-2023 The ENDO Fix LLC. All rights reserved.

Patient Centered Endodontics: The Rehabilitation of Compromised Teeth

Blue Light Special

Daily Fix

The intersection of scopes, filters, composite, and light can lead to some confusion and possibly unsafe clinical habits. So lets get the whole story straight and make sure our working habits are healthy as well as productive.

Light cure composites set when they are exposed to a light energy at a set wavelength of light. The composite has a photo-initiator called camphorquinone and an accelerator. The activator present in light activated composite is diethyl-amino-ethyl-methacrylate (amine) or diketone. They interact when exposed to light at wavelength of 400-500 nm, i.e, blue region of the visible light spectrum and cause the composite to set.

Sunlight, ambient light, and all other white light have the entire spectrum. So in the operatory, the ambient light will have enough blue light to make composite eventually cure. And your scope light with all its fabulous power will totally cook your composite. Additionally, the blue light with its low wavelength and high energy has the potential to cause harm to your eyes. Macular degeneration, retinal problems, and possibly cataracts are on the table eye damage wise. In addition, blue light is believed to affect mood and sleep among other things. Fortunately, there are filters that filter out the blue light.

Looking at the color wheel which represents the colors (ROYGBIV) and their opposites, you can see the opposite of blue is orange. So these orange filters will filter out the blue light.

Which comes in super handy when working under the scope doing composite work:

We do all our bonding using the orange filter in the scope. And here’s where some people get bamboozled.

Awash in orange light it’s easy to think that your scope filter is protecting you during the cure process.

Oh contraire monfraire!

If you were to remove the light from the back of the scope, and hit a cure, you’ll notice there is no difference whether the filter is applied or not.

The filter isn’t in the column at all. Its where the fiberoptic/liquid cable enters the back of the scope.

It’s this little guy here…

So when it’s time to cure, either look away out of the scope or don some protective eye wear.

In the case of performing a custom resin matrix, its eye wear for the both of us. Routine composite work, I usually just close my eyes till I hear the beep.

Decoronation of an Ankylosed Tooth

Weekly Fix

Decisions…decisions. A very young looking 10 year old girl presented after an avulsion of tooth number 9 with a very short extra-oral dry time, immediately replanted and subsequently splinted. The decision of whether to initiate endo on the central is dictated by the time out of the mouth and the development of the tooth. I made the call that the apex looked wide open and the tooth hadn’t completely developed. So we decided to wait and see if the tooth would revascularize. My first follow-up time of trauma is typically 3 weeks. I saw her inside of 4 and resorption was already full on; progressive and aggressive. Classification wise this would be external axial resorption. We initiated endo immediately, but the damage was done. Additionally, the concussed lateral wasn’t responding to cold, so we started endo on that one as well.

We kept the tooth in medication for 5 months changing it out monthly. Over that period of time there was ankylotic tone and no mobility under the scope using 2 mirror handles to evaluate. Ugh. We placed Vitapex in the canal which lasts longer than many other CaOH preparations, and restored. Over time, washing out of the medication could be observed; a common finding in a resorbing root. We waited until we measured 3mm infra-occlusion and set her up for a flapless decoronation like my buddy Buck came up with circa 2008.

If you can, preserve the pulp. If you can’t; save the root and tooth. If you can’t do that, at least save the bone. That’s where decoronation comes in.

We clamped the other central and split dam to the distal of the lateral and used a rubber dam triangle to wedge the dam distally. Then we cut the crown off using a an 014 tapered diamond. Then a surgical length 556 on end, we cut the tooth flat to 1-2mm below the bone. It’s critical to remove all the enamel as it won’t resorb. We observed granulomatous soft tissue extending from the canal space. A good clot was evident before dismissing the patient.

Hindsight being 20/20 I woulda medicated the tooth at a week. Similar patient representing the same way? That’s tougher. I’m thinking if the tooth looks most of the way developed, regardless of the apex developement, I might jump in. It’s a tough call.

Dens Invaginatus

Daily Fix, Large Lesion

Sometimes the development of the tooth goes a little haywire and another tooth begins to develop within a tooth, but not completely. So we end up with this invagination leading to the pulp and sometimes it doesn’t completely close off. Such a situation set the pulp up for an early death as can be seen here by the lack of root development and divergent open apices. Here we have a a pretty large finding imaging wise and a swelling. We changed the calcium hydroxide medicine out over 5 months and ultimately filled the apical 5mm with MTA and then reinforced the rooth with a fiber post. At 4 years post op there appears to be complete radiographic clearing and retained radio-opacity from the calcium hydroxide.

System S

Tips, Tricks, and Hacks

When your filling with rubber you got options. Carrier based, cones, and System S, otherwise knows as the Squirt.

I first learned of the Squirt from Joey Dovgan in 2008 whilst at Einstein and while I didn’t consistently squirt until a few years ago, there would be some cases that I would employ the method when I felt appropriate. That changed some when I introduced “enhanced irrigation” aka the laser in my case to our practice. Like Joey said back in the day, the most important part of filling is actually the instrumentation. However, I would submit that neither deep shape nor continuous taper are necessary to get consistent fills. But, the capture zone in the apical 1/3; that is pretty important.

Regardless of your system with system S, your going to have to live with some variability. That’s the rub. It’s easier, faster, displays some cool anatomy, but sometimes its a bit on the splashy side. And that’s not for everyone. And finally, you gotta be careful in the posterior mandible when the apices of lower teeth approximate the mandibular canal. The CBCT is your guide in such cases in it’s ability to determine anatomical positioning.

But the typical case is often amenable to System S. Instrumentation wise, system S works well with Rootform Appropriate Instrumentation. Typically the main difference with instrumentation is that I will typically take rotary instruments 1 full mm from the 00 on the EAL as opposed to .5mm when I cone-fill. During the course of treatment the laser is employed and final series of enhanced irrigation performed (3 min of sweeps with Hypo and EDTA). Patency is confirmed with a 15K file before the final series. A final rinse with alcohol makes for expedient drying of the tooth. Medium paper points are used and should not sail long. If they do, then consider an alternate filling technique. Generally speaking I would move to a cone. And if a 40.06 cone goes long, I’m considering MTA. When the cones are dry, AH+ sealer is applied to a medium paper point and used to coat 1-2 canals. More canals require another coated paper point. Then one or two dry paper points per canal to remove the excess. If your fills are two splashy, dry more.

The OG’s of squirt will tell you Schwed in an Obtura is the way to go. And that’s fine. I prefer the Calamus with the thinner gauge tip. They fit great into the instrumented canals. But like many things the old school Calamus are made with a better plastic and are more durable. Most times just placing the tip and allowing the machine to back you out of the canal results in a great fill. Not surprisingly, if you want to plunge the gp after application, Joey D’s niti pluggers are the best. Unfortunately, they are no longer made but perhaps you can find one on the after market.

In Type 2 canal systems, the gp can get hung up where the canals join and not proceed to the terminus. You got options though. Block one canal with one plugger, then plunge the other with another plugger (whilst moving the first to the mirror hand- yes your hand can hold two things). Or block one with a plugger and use the calamus to force-fill the other. Both work. I still take downpack films which are neither films nor the result of any downpacking, but usually I can’t wait to get my thrill of the fill, even after filling well over 10K teeth.

Portal

Daily Fix

Amalgam is a great material because it’s not technique sensitive. When done well it stands up to quite a bit of abuse and hostility from the patient. Here we can see the whole distal dislodged. And while I can’t remember it ever happening to one of my buildups, I want to prevent it from happening. So I began, when reasonable making a portal that ties the distal component to the internal frustum core. A massive macromechanical retention feature. The result is this little triangle of tooth coronal to the circle in the second image. And yeah, I usually bond these big amalgams for belt suspenders as well as maybe some anti fracture attitude. The early portal cases naturally led to the double entry truss cases that followed.

Internal Approach

Daily Fix, Resorption

This tooth presented with inter-proximal external crestal resorption according to my resorption classification for clinicians. Usually I like to have an external surgical approach to ensure clean margins, manage the field, and work the appropriate matrix. However, an external approach here would have left one hell of a periodontal problem and lots of bone destruction. So, we worked it out internally. Ultimately, glass ionomer was used as the restorative choice here. On short termish recall, the perio tissues look great- 3mm probings all around and no bleeding on probing. So far so good, no resorptive recurrence.

Root Form Appropriate Instrumentation

Daily Fix, Deep Fix

Contextualizing with history here is kinda important. As many of the old timers are calling it quits, it may be of benefit to put this down for the next generation of pulp slaying tooth fixers. The story goes like this. There was an observation that failing endodontics was associated with poorly root filled teeth. The following Schilder inference follows, namely: “Inadequate obturation of the root canal invites failure.” So the focus laser beamed on the fill and it’s associated process centered outcome. In order to employ the warm gutta percha technique, the root canal must be shaped so that a continuously tapering funnel is created with its narrowest diameter at the periodontal ligament and its widest diameter at the coronal opening or access cavity.

Back then they were doing this shaping by hand with reamers. And they had these stainless heat pluggers that looked like a spreader that they heated to a “cherry” red before “sheparding’ the gutta percha into the canals with graded stainless pluggers. So in order to get the pluggers to fit, they had to shape the canal to fit the graded pluggers. “Whala”, the continuous taper was unleashed and the rotary revolution followed suit. “Deep shape” became a thing and a lot of root dentin went down the drain. Observationally, we saw some of these break and wondered if maybe all that shape was necessary. Not to mention the strip perf’s. The first to make a change was Buchannan with GT files which at least had a maximum flute diameter. SSW under the direction of Khademi made the biggest leap a decade ago with variable taper instruments. That made things soooo much easier.

Out went shaping, deep shape and in came dentin conservation. Because, well, did you ever find anything that got stronger by whittling on it? Me neither. And yet we still had length control and root filling to contend with and accomplish. That led to the idea of rootform appropriate instrumentation. The balance of not hogging the tooth, and still accomplishing what was necessary. The apical taper kept the fillings from going long and the variable taper kept from too much coronal hogging. Using imaging and knowledge of root anatomy to guide the instrumentation was central to this approach. Using a thoughtful approach to balancing necessary and sufficient notions of root dentin removal achieve the desired process centered outcomes of the operator is the grounding principle behind root-form appropriate instrumentation., Generally speaking as long as the teeth were of average length and didn’t have extreme curves the following could be somewhat prescriptive as long as the prior principle is kept in the forefront of one’s mind and the driver doesn’t fall asleep at the wheel.

So prescription wise there are a number of great instruments out there. What I kinda landed on were three different instruments of different tips and tapers. Namely 17.04V (grey) , 20.06V (yellow), and 20.07V (blue) the V standing for variable taper as none of these are continuous taper instruments. The 17.04 and 20.06 I use are heat treated SSWhite instruments the 20.7 is the F1 by Tulsa which can be obtained in heat treated as well in their gold line. There are lots of F1 substitutes out there if your not a Tulsa fan. The colors here refer to the final file used. Longer roots than the average will typically mean dropping back a size.

This was all a decade ago, before tech. What’s necessary for tech? Probably less; hopefully less, maybe even none one day. There’s some evidence that the move to lose some weight from the continuous taper days has had some benefit in outcomes at longer time frames ie less breaking failures. Are there diminishing returns for losing additional weight, and whittling even less? Harder to tell. Maybe. Harder to root fill? Definitely. The instrumentation appears to approach some conservative silver point preps from the age before rubber or even smaller, considerably smaller with tech ended instrumentation.

The left image is presented with permission from a Shilder trained endodontist. The right was what I was trying to accomplish at the time highlighting root-form appropriate instrumentation as a pillar of Restoratively Driven Endodontics a decade ago. There are still tons of continuous taper rotary systems being employed today, pleasing the dopamine release centers of those enamored with “the look”. Countering those emotions are our own visceral response when we see extraction pending teeth that were given the deep shape death sentence.

Canine Dens

Daily Fix

Dens in dente are a relatively rare tooth deformity. Canine dens are particularly rare. The dens or “tooth within a tooth” presents problems in that the canal systems are highly irregular, challenging to disinfect, and difficult to fill. Often times surgery is necessary. In this case we were patient with the patient, used calcium hydroxide for a while and got a good result. Glad they aren’t all like this. Complete resolution in 3D with my eyes.

Titanium Decision Making

Daily Fix

I’m not really even going to get into the decision making generally speaking with regard to the bridgework that cantilevers with two premolars off the back end of the canine, but doesn’t connect to the molar. But, I’m thinking that such a person used similar thinking with regard to their post choice. Radiographically this is either fiber or titanium. On access I confirmed titanium and then closed up shop and reappointed for the surgery. Unlike fiber, they can’t be drilled out, and unlike other metal posts they don’t vibrate out well, so the result of removal is coronal carnage. Thus the decision to whack.

Similar thinking led me down the road on this recall from a different patient this week. Bone fill at 6 months looks great with my eyes.

Lets leave the titanium to the implant specialists.

J- Shaped Retreatment

Daily Fix

This gentleman presented with pain and swelling as well as probing to the apex on the distal aspect of the tooth. Many people would say the tooth was cracked. But we’ve saved many, many teeth that fit this profile. J-shaped ragiographic findings are not pathognomatic for cracked roots. The the embrasure right with the tipping of the back tooth will be tough. Amalgam is a better choice when we are down on bone with potential contact issues in the future. Removing fiber posts if you have a chairside assistant in the scope is a breeze. The tooth had some reasonable buccal and lingual tooth structure so it makes it a decent retreatment candidate when following the Retreatment Algorithm.