Your Endodontist as a member of your Restorative Team

Your endodontist can be a valuable member of your restorative team. You can rely on your endodontist to support and reinforce your appropriate treatment plan.

As an endodontist, I want to see two things happen for my patients:
1. Endodontic therapy be successful
2. Patients value and retain their natural teeth

1. Endodontic therapy be successful:
Everyone knows that successful endodontic therapy requires proper coronal restoration. Without adequate restoration, even the best endodontic therapy will fail. As endodontists, we are invested in the successful treatment of the tooth, therefore, we will always encourage the patients to have their endodontically treated teeth properly restored. That means uncrowned posterior teeth and teeth with large restorations getting coronal coverage to protect them from cracks and fractures and current crowns/bridges with leaking margins/decay replaced to prevent coronal leakage. When a patient leaves my office, I make sure to let them know that they need to protect the root canal against bacterial leakage and occlusal forces. If our patients have been educated correctly, they will return to your office and ask for their new crown or bridge.

This patient came into my office today hoping for a root canal and a filling to preserve this bridge. I encouraged the patient to place a new bridge to prevent coronal leakage following endodontic treatment.

2. Patients value and retain their natural teeth:
I frequently see uncrowned posterior teeth with large restorations, craze lines & cracks. These teeth, especially in patients who are bruxers or have severe patterns of occlusal wear, are at risk of splitting the tooth. I encourage them to talk to their dentist about crowns to protect those teeth before they are damaged and become non-restorable. I hate to tell patients that they need an extraction because the tooth has split in half.




The general dentist has the primary responsibility for treatment planning. Your endodontist can play an important part of your restorative team by helping to educate your patients on the importance of proper restoration following endodontic treatment and the importance of proper restoration to prevent cracks/fractures.

The Split Tooth - A Cracked Tooth Gone Bad

Talking about cracked teeth is sometimes confusing. There are several types of cracked teeth. The treatment and prognosis of a cracked tooth depends on the type, location & severity of the crack.

Types of cracked teeth include: craze lines, fractured cusps, cracked tooth (restorable type and non-restorable type), split tooth & vertical root fracture.

A split tooth is caused by a cracked tooth that has gone untreated over a period of time. The tooth is literally split into two pieces by a crack that runs through the tooth. A tooth can be split mesio-distally or linguo-buccally. The crack of a split tooth includes damage to the root itself. The crack of a split tooth can be seen crossing the floor of the pulpal chamber. This is a sure sign of a non-restorable tooth.

The following case is an example of a split tooth.

This patient presented for endodontic therapy. #15 had a small occlusal amalgam. The tooth is diagnosed as necrotic with symptomatic apical periodontitis.

Close examination of the occlusal surface shows a stained crack on the mesial & distal marginal ridges. You can see that the lingual and buccal surfaces of the tooth have been flexing for an extended period of time. The clinical appearance of this tooth strongly suggests a split tooth.
In this case, the patient was informed of the probable non-restorability of this tooth.

Removal of the amalgam shows the connection between the MMR & DMR cracks. The argument for a split tooth becomes even stronger.

After access into the pulpal chamber, the cracks can be traced down the mesial and distal walls and then connecting across the pulpal floor. The diagnosis of split tooth is now confirmed.

Just for fun, transillumination is used to show the cracks.

Tooth was referred for extraction.

Source: AAE publication

Diagnosing Root Fractures

Diagnosis of a vertical root fracture is very difficult. It sometimes frustrates me to see how quickly some people diagnose a root fracture. I tell my patients that I like to rule everything else out before I make that assumption. I say assumption, because unless you can visualize the root fracture, you are making an assumption.

There are some clinical signs that can be associated with a vertical root fracture, however, they are not 100% diagnostic of a vertical root fracture.

For example, a long narrow periodontal pocket is often associated with a vertical root fracture. The periodontal attachment breaks down along the fracture line, creating this defect. However this same type of narrow periodontal defect can also be caused by an abscess draining through the periodontal ligament.



A j-shaped lesion is often associated with vertical root fractures. However, not all j-shaped lesions are fractured roots.

In this case there were no fractures found. Complete resolution of these lesions is expected.







If visualization of a vertical root fracture is the most accurate way to diagnose a root fracture, how is that to be done?


Visualization of a fracture is best done using a microscope. A microscope with a light source will allow you to see fractures during endodontic treatment.

A microscope will allow you to determine if a crack goes down past the CEJ and into the root
or if it crosses the pulpal floor.

Visualizing a crack running across the pulpal floor of the tooth is (on left) is a 100% accurate diagnosis. This tooth must be extracted.










This is another example of a crack running along the floor of the pulp chamber from the MB root to the Palatal root of a Mx first molar.












In most cases, I prefer to verify a fracture before extraction. This is time consuming and not very profitable, but I believe it is in the patient's best interest. This is also the course I would take if it were my tooth.

Fractured Tooth

This patient came in today with a necrotic tooth #14. She had a draining sinus tract on the palatal and recounted a history of massive palatal swelling. Diagnostic tests found #14 Necrotic Pulp with Chronic Apical Abscess.
The tooth had a MO amalgam & O amalgam. Patient also has a history of bruxism with cuspal fractures on other teeth.

Upon access, a crack running down the distal wall and a crack running down the mesial wall both took a left turn and met across the pulpal floor. This tooth was then diagnosed as non-restorable and an extraction was recommended.
Had this tooth been crowned previously, it may have been saved. When patients exhibit severe patterns of occlusion with bruxism, I would recommend cuspal coverage at an earlier stage.
If you have difficulty making this recommendation to your patients, I would be glad to send you some pictures from my photographic collection called, "Teeth that might not have fractured if they had been crowned". You could make a nice picture book with these photos.

Cracked Teeth

Here are a few teeth that I have seen in my practice. Some of them were treated endodontically, and others simply needed cuspal coverage. It is my recommendation that when you find teeth like these, that have cracks and signs of stress, that you recommend cuspal coverage. Before crowning them, I would recommend a thorough endodontic evaluation, including percussion, biting (tooth sleuth), probing and thermal testing to evaluate pulpal status. If the tooth passes all of these tests and the pulp is normal, then I would recommend cuspal coverage.

Even though these amalgams are conservative, multiple enamel cracks are evident. Signs of stress are everywhere. This tooth needs cuspal coverage before it becomes necrotic, fractures a cusp, or develops a fractured root.

Cracks like these through the marginal ridges generally extend down the pulpal wall.

When you find a tooth that has cracks on the mesial and distal marginal ridge, the tooth is under extreme forces. If left untreated, the buccal and lingual sides of this tooth will continue to flex and the cracks will eventually meet in the middle and the tooth will become non-restorable.

I'm no practice management guru, but I know if you identify the cracked teeth already in your practice, do proper endodontic evaluation, and protect your patient's teeth with cuspal coverage, you will be doing them a great service and building your practice at the same time. If your patients question the need for cuspal coverage of cracked teeth, send them over for a consultation with your endodontist. We see teeth everyday that could have been saved if they had only been crowned earlier.

This last image is what I call the "Past, Present & Future Cracked Tooth". Past (#3-extracted), Present (#4-buccal cusp fracture), Future (#5-MMR crack waiting for buccal cusp to fracture). Proper diagnosis & treatment will save your patients time and money.

Cracked Tooth

When a crack extends from the occlusal (chewing) surface towards the root, we call it a cracked tooth. These cracks may be very small or very large. The crack often causes damage to the pulp of the tooth. Primary symptom of a cracked tooth is pain upon chewing. This pain may be irregular and sporadic.

The depth and position of the crack determines whether the tooth is restorable. If the crack is in the coronal portion of the tooth, then placing a crown with prevent futher flexing of the tooth as well as prevent bacterial leakage through the crack.

A crack extending down the root surface is also commonly referred to a root fracture. Root fractures can be difficult to diagnose. Often they are associated with a deep, narrow, periodontal defect. However, a draining abscess can also cause a deep narrow pocket, which can easily be confused with a root fracture.


In the picture above, the extracted tooth has been dyed. The periodontal ligament picks up the stain. You can see that in the area of the crack, the pdl has broken down and a deep, narrow periodontal defect has developed on the line of the crack.

A cracked tooth that is not treated will worsen and lead to loss of the tooth. Early diagnosis and treatment are essential in preserving these teeth.

Transillumination

Transillumination can be a useful diagnostic tool for identifying cracked teeth. As the light passes through the enamel, a crack will diffract the light and make the crack visible.

In this case, tooth #19 has visible cracks on the lingual, buccal and disto-marginal ridge.

This may be an important tool to help you identify a cracked tooth. Accurate pulpal and periapical diagnostics are most important to determine if endodontic therapy is needed before a crown is placed.
Transillumination helps the patient to see the stresses that the tooth is under and realize the importance of coronal coverage.

Cracked Tooth?

This patient came in today complaining of pain on #31. I went through my typical diagnostics and diagnosed the tooth as: partially necrotic pulp with phoenix abscess. The patient elected to go ahead with endodontic treatment today, since she is leaving town tomorrow morning.

Once I opened up the tooth, I realized that there was a crack on the distal of the tooth. I proceeded with the access and removed all the distal amalgam to get a good look of the crack. I wanted to find out if the crack was just in the surface of the enamel or if it went all the way through the dentin. I found some purulence in the distal canal and bleeding in the mesial canals (confirming my diagnosis of partially necrotic). Once I got the access opened up, I could see that the crack ran down along the distal wall of the pulpal chamber. When I find cracks like this, I think that it changes the long term prognosis of the tooth. We all know that the research supports the survival rate of endodontically treated teeth (when properly restored) at very high levels (90+%). A crack in the tooth is a factor that will likely decrease that long term survival rate. However, I have found that even in a situation like this, when given the options, many patients still want to try and save their tooth.

This is what I found. At this point in the procedure, I stop and we have a little "heart to heart". I explain to the patient what I have found. Then I tell them that their options are:

1. Complete the RCT, restore, and recall. I explain the decreased prognosis. There is really no evidence/research (I am aware of) that would tell them how much a crack in the tooth will change the long term prognosis.

2. Extract the tooth. Replacement options are discussed. In this case, with a full complement of teeth, an implant would be the only practical replacement option.

In this particular case, the patient decided that she did not want to extract the tooth. With good informed consent we completed the case, reduced the occlusion & temporized the tooth. She will return to her G.P. for build-up & crown. You may see that I removed a little extra gutta percha from the distal canal, to allow the bonded restoration to seal off the distal a little better.

Here is how the final film turned out.

We will recall her in 6 months to re-evaluate the distal lesion. I really feel that the key to this type of treatment is informed consent. When presented the options & prognosis, some patients will elect to extract and move on. However, most patients want to try and save their natural tooth. Endodontics can help them retain their natural teeth for many years.

Here is another case where a cracked tooth was found and it was recommended that she extract the tooth and have an implant placed. The patient followed the recommendation and had tooth extracted, bone grafting, and an implant placed by a specialist.

4 years later, she returned for re-eavluation. The implant was loose, probed to the apex, and there was purulence. You have to wonder if it wouldn't have been better to have tried to save the tooth originally. I can't guarantee that the tooth would have lasted with endodontic treatment, but it is an option that shouldn't be left out of the treatment planning process.