The Endo Fix

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

Patient Centered Endodontics: The Rehabilitation of Compromised Teeth

Root Tip Endo

Weekly Fix

Consider these observations:

Chesapeake Endodontist
Suffolk Endodontist

These are but a few of the many documented cases of root tip endos that I’ve seen over the years in practice. The patients are all asymptomatic, albeit clearly not functional. We can see food, plaque, and caries sitting on the root filling. These roots have been infected for years. If we were to say that there was some sort of threshhold of bacteria that need to be removed to have a favorable endodontic outcome; these teeth would represent the maximum, most bacteria filled, most infected roots possible. And as such these teeth should have both clinical symptoms of pain and swelling as well as radiographic signs of endodontic pathosis. However, all of these patients are asymptomatic. And radiographic interpretation suggests they are typically free of apical findings. How could it be that the most infected roots have no radiographic findings? It must be something more than just the presence of bacteria or some degree of bacteria in the root of the tooth that defines endodontic pathosis.

Perhaps the lack of occlusion on these roots has something to do with it. If this is true, as the available evidence suggests, then occlusal function plays a role in “endodontic pathosis”. Such a supposition isn’t terribly surprising in that occlusal parafunction can lead to endodontic necrosis in the absence of caries. Furthermore, many of the signs and symptoms traditionally associated with infection related endodontic pathosis can be associated with occlusal parafunction even in the absence of infected roots or proximal caries. Thus, the myriad of endodontic conditions that present in clinical practice are not well explained by the apical periodontitis disease model and the relationship between radiographic findings and endodontic pathosis is not a direct one.

Post or No Post?

Daily Fix
Newport News Endodontist

A pretty common question that comes up when I’ve lectured on restoring endodontically treated teeth is “Do molars need a post?”. I would say, on most initial treatments, the answer is no. Reason being, with a conservative access, the internal access shape is convergent leading to a frustum shaped access which lends considerable retention. In some cases, what your dealt, has already compromised this retentive form. In this root tip endo case, the root filling had been exposed for a long time, and with regard to remaining tooth structure- it already had 3 strikes. The patient knew that this tooth didn’t have a favorable long-term prognosis but wanted to buy some time. So, we pitched a tent with 3 stainless steel posts and placed a bonded amalgam. A little heroic? More or less heroic than Nacho Libre?

Margin Salvation with Retreatment

Daily Fix

Hampton Roads Endodontist

It’s always a little disheartening when we access into a bridge abutment to find rampant caries. The patient wanted to get some more time out of the bridge. We we removed all the cariest, retreated the tooth, and flushed up the margin with amalgam. We saved the bridge for at least a year, with no signs of caries so far.

Surgical Treatment of a Lateral Canal

Daily Fix

Suffolk Endodontst

Six year followup of an apical and lateral surgery. The CBCT, even with the significant artifact, suggested lateral bone loss. This could have been attributed to a fractured root. However, in this case it was related to a lateral canal. Both lateral and root end preparations where made, and root filled with grey MTA. Complete healing is evident at the six year mark.

Getting Sideways

Daily Fix

Suffolk Endodontist

Super sideways molar positioned because the premolar never erupted. The area is kind of a food trap, but the patient wanted to keep it. The margin here was so deep the matrix wouldn’t reach. So we packed Cavit and flowed some Dycal over it to finish the matrix. It took me 3 appointments to finish this 28mm monster.

Resolved.

Daily Fix

Suffolk Endodontst

Experience has led some clinicians to the conclusion that large areas of apical bone loss can’t be managed without surgical intervention. And in some instances, that may be the case. However, often, in large areas of apical bone less where the cause is endodontic in nature, nonsurgical endodontics can provide a predictable and favorable outcome.  In this case, there was a history of trauma to the maxillary incisor. The apical finding is larger than a centimeter in diameter in both the buccolingual plane and inciso-apical plane (A,B). The tooth was accessed and medicated with Calcium Hydroxide for a few months. When initial signs of healing were observed radiographically, the tooth was obturated and restored. At two years, complete healing can be observed both in 2D and 3D (C,D). Large areas of bone loss can provide treatment planning challenges in the esthetic zone. In addition, many patients are taking medications that put them at risk for bone necrosis of the jaws when subjected to surgical interventions. Often endodontics can help in managing these situations.

Considering Revascularization, Regendo

Weekly Fix

 

Suffolk Endodontst

This was a regendo case, or at the time almost 10 years ago we revered to these cases as revascularization. This tooth belonged to a young Asian girl who had a dens invaginatus. We also had to do the contralateral tooth as both became necrotic. She presented very swollen as a result of this infected tooth. We placed a mix of antiobiotic paste in the tooth for two to three weeks. At the second appointment after rinsing out the antibiotic mix, we used a file long with a little EDTA. A collagen matrix was placed, so that it wicked blood above the CEJ. Grey MTA was placed as a barrier above the collagen, and then the tooth was restored with composite. Axial root development occurs although not much at the level of the CEJ. At the time there was hope that regenerative endodontics could continue root development leading to stronger teeth that could last longer.

Chesapeake Endodontist

The forces of anterior teeth are different than posterior teeth. As such, structural failures often result in “snap off” failures at or about the level of the CEJ. Axial dentin in this area or as Clark and Khademi define pericervical dentin (PCD), is the predominant structure that defends against this type of force and prevents snap off failures. My good friend and co-resident David Prusikowski won a prize for a revascularization poster where the management was applied to an anterior tooth. Unfortunately for the patient and the subject and poster, the tooth snapped off not long after the prize was awarded.  The mix of hard tissue is somewhat unpredictable, and while some root lengthening, or some apical development may occur, it is very rare to find cases where PCD was increased in any real way.

 

Hampton Roads Endodontist

This is an interesting case where I learned a few things. The patient presented with swelling and had a history of trauma. Given the development of the tooth we opted to try a regenerative approach to build some dentin strength and add for some longevity. At the time the patient requested her restorative dentist place the filling and we obliged. In this case we used calcium hydroxide instead of the bimix as the recommendations had changed. We still used collagen and MTA though. The tooth was restored by her dentist. After 4 years we can see some apexification. However, no PCD acquisition was evident.

Suffolk Endodontist

The patient returned with symptoms of acute percussive pain on the tooth. I thought it odd as there was boney infiltrate throughout the canal. Regardless it was prominent and repeatable. Additionally, staining of the MTA was observed. So we decided on a revision. A significant void was noted over the MTA on re-entry. After the MTA was removed, bone was observed just below the level of the MTA, at the level of the CEJ. Calcium hydroxide was expressed into the canal amongst the bone infiltrate. Over several appointments, the bone was removed by devitalizing it with calcium hydroxide, ultrasonics, and small burs. The tooth was also bleached to remove the MTA staining.

Eventually we were ready to obturate, and grey MTA was placed apically.

 

 

We inverted a fiber post which we bonded in with a dual cure buildup material and placed a few accessory posts. We trimmed back the posts and provided a “Clark cala lilly preparation” which creates long bevels in enamel before restoring with composite.

So, in considering the number of these types of cases that I’ve done over the years as well as how anterior teeth most often fail, I think taking the benefit of fiber post reinforcement is often preferable to revascularization as the regendo cases don’t predictably create PCD. There are a few cases types though, perhaps with really divergent apices where it may be the only choice. But by the time most of these teeth hit the mouth, they have enough development that tilt the decision in favor of fiber reinforcement.

 

 

Trauma, Resorption, and Decoronation

Resorption, Weekly Fix

Suffolk Endodontist

This little guy caught a fly ball… in the mouth. The lateral was laterally luxated. The central was avulsed and replanted with a dry time of 15 minutes. The lateral was repositioned and splinted. I saw them the day after the injury. We made sure he was on an antibiotic and anti-inflammatory and saw him back in a week to start endodontic therapy as the apex of these teeth were completely deveoloped and the risk of resorption high. After what we thought was a sufficient time in both CaOH and splint therapy, we completed the endodontic therapy and placed fiber posts.

Newport News Endodontist

Over the next few years we saw resorption develop. According to the Resorption Classification for Clinicians, this resorption would be considered External Crestal Resorption, moderate scooping. We removed the invasive tissue and restored the root using composite. A custom resin matrix was used for isolation.

Hampton Roads Endodontist

Over time, we could see that the central was subject to resorption as well; External Ankylotic Resorption. This was evident by the ankylotic tone when percussed. Radiographically, this was evident my the marked lack of periodontal ligament and lack of tooth root definition. Clinically, this was evident by the infraposition of the clinical crown relative to the other central.

Root Canal Expert

In treatment planning the case, the orthodontist thought some initial leveling and aligning using the ankylosed tooth would be helpful before decoronation. After this was accomplished, the fiber post and root filling was removed and the crown was decoronated using the flapless decoronation approach as outlined by Jared Buck in Best Practices: A Desk Reference

Chesapeake Endodontist

A pontic was added to the orthodontic therapy.

Harbor View Endodontist

We can see over time that bone developed over the tooth root and the the root is turned over in osseous regeneration. The alveolar ridge is preserved for future restorative replacement.

Hampton Roads Endodontist

Here’s the 5 year followup.

Resorption Classification for Clinicians

Deep Fix, Resorption

Historically, classifying systems for resorption have been insufficient to adaquitely guide the treating doctor and inform decision making in the clinical management of resorption . Words like inflammatory and replacement as identifiers are less than ideal as all resorption is inflammatory and all resorption involves replacement.  Identifiers using cervical when used to describe ECIR are not really accurate either and are really misleading as the resorption typically stems from the level of the crestal bone. For these reasons, based on more current models, I use a clinical model of classifying resorption, and subsequent management thereof:

Hampton Endodontist, www.endovirginia.com

The initial identifiers are based first on the derived process location- either external or internal. It’s important to note that the identifiers are derived from imaging, most often CBCT imaging.

Internal Resorption is derived from the pulp. The presentation can be with either a vital or necrotic pulp. Additionally, the resorption can be further classified by extent- namely non-perforating, or perforating. Internal Resorption that is perforating may require surgery to adequately manage the case. Often the process involves a vital pulp, however, occasionally, the pulp may be non-vital. From a prevalence perspective, internal resorption is low; its rare. With internal resorption, since the process is pulpally derived, the replaced tissue is radiolucent. There is not a bone deposition component to internal resorption.

Internal resorption with a necrotic pulp:

Suffolk Endodontist

Internal Resorption with Perforation:

Tidewater Endodontist

External resorption refers to the process of tooth structure being removed and replaced from the outside. Additional identifiers depict distinctions based on a mix of location, cause, and extent. External Crestal Resorption is by far the most common type of resorption. It originates at the level of the crestal bone. A mix of soft granulomatous tissue and hard boney tissue invade and replace the tooth. Additional identifiers include scooping or tunneling. Scooping refers to the pattern of extension by which it progresses in a relatively bowled out fashion as if the tooth removal was performed with a small ice cream scoop. Tunneling refers to a thin fingerlike progression, often many of them progressing axially. Finally, the extent of the External Crestal Resorption may be described. Mild refers to external resorption that doesn’t involve the pulpal space. Moderate is likely to involve the pulp space and will require endodontic therapy. Severe resorption is the extent whereby the tooth is usually no longer restorable. The determination of restorability is made via CBCT. One thing to keep in mind when determining the extent of the resorption is the hard tissue component invading the tooth. It’s easy to mistake tooth schema for invading bone or bone schema. Additionally, the pdl is not present in this area making the distinction more difficult. Sometimes, changing the scale of the imaging during viewing can help. that’s because the process of interpreting schemata is itself dependent on scale. For example, we understand that mouth is part of face, and lips are part of mouth, and vermilian border part of lips. Changing the scale helps with understanding features at all levels.

External Crestal Resorption, Moderate Scooping:

Suffolk Endodontist

External Crestal Resorption, Severe, Tunneling:

Tunneling Resorption presents challenges as the osseous tissue embeds itself axially. Aggressive removal weakens the tooth, however, leaving bone behind allows for resorptive progression.

External Apical Resorption:

Chesapeake Endodontist

External Apical Resorption can be a result of orthodontic force, root canal infection, or in some cases, unknown causal relation.

 

 

External Pressure Resorption:

Chesapeake Endodontist

Teeth and expansile growths such as cysts can cause pressure resorption. Depending on the restorability the extent may be mild, moderate, or severe.

External Axial Resorption:

Hampton Roads Endodontics

External Axial Resorption is identifiable by the radiolucent areas adjacent to root structures. Often this is sequela of trauma and accompanied by an infected tooth. This resorption may be arrested by endodontic therapy and medication with calcium hydroxide. The extent of the injury and development of the tooth determines the prognosis. Often injuries to these teeth include avulsion, lateral luxation, intrusion or extrusion. Depending on the extent of External Axial Resorption, External Ankylotic Resorption may follow over time.

 

External Ankylotic Resorption:

Newport Bews Endodontist

External Ankylotic Resorption may follow after External Axial Resorption. The difference is the lack of radiolucent areas adjacent to the root. As with other external resorption where bone deposition is involved, distinguishing between root and bone schemas can be difficult. The appropriate interpretive response is increased uncertainty. In the developing adolescent, when facial development is not complete, the management of External Ankylotic Resorption is decoronation. An alternative might include autotransplantation if there is a knowledgeable and skilled surgeon.