When you take a radiograph or any dental image for a patient, are you only paying attention to the “problem tooth”? It’s so easy to get tunnel vision when we look at radiographs, but that isn’t the whole tooth story! It’s critical to go beyond the obvious issue and carefully examine every radiograph and cone beam you take. Often, it’s this wider vision that allows us to find the root of the problem (pun intended)! This root resorption treatment tooth story is a perfect example of this phenomenon. 

The Root Of The Problem

It was obvious from the radiograph that Tooth #19 needed treatment and root canal therapy—it had no response to cold and was tender to percussion, so I diagnosed it with a Necrotic Pulp and Symptomatic Apical Periodontitis. (For the record, all probings were within normal limits, as well.)

But Tooth #19 wasn’t the only problem here. If you take a look at the other teeth in the quadrant, you’ll also see signs of resorption in Tooth #20. 

When I perform a root canal, one of my standard operating procedures is to take a CBCT on the treatment tooth beforehand. My main purpose here is to understand the tooth’s true anatomy, so I don’t leave any canal untreated. Over the years, my CBCT has revealed the whole tooth story to me time and time again. In this case, I knew the CBCT would be the perfect opportunity to check on the other teeth in the quadrant for any other type of pathology. 

One of the tricky parts about using a CBCT is that depending on your view and the angle of the slice you’re using, things can appear normal. This next image is only one slice of the sagittal view. 

As you can see, the axial view shows evidence of resorption on the lingual surface of #20—but it also shows the same kind of resorption on Tooth #21. This type of resorption that occurs on more than one tooth is called external cervical invasive resorption. It originates from the outside, and invades inwards to occur on the cervical aspect of the tooth. To fix it, I’d need to perform external resorption treatment.

The Challenges of Root Resorption Treatment

Resorption can be a real PITA. Since patients usually don’t experience pain with it, and it can go undetected on radiographs, dentists often miss it. So, when I notice it in one location of the mouth, I always double check for signs of it in other locations—particularly on the contralateral side. 

Resorption isn’t JUST difficult to diagnose. Root resorption TREATMENT is challenging, as well. If you look at the tooth from the coronal view, you’ll notice the location of the resorption is a little improved, making it easy to understand why we call it external cervical resorption. This resorption is at a relatively early stage of progression, but its location at the crest of bone and on the lingual makes it tricky to access.

Resorption Classifications Review

Before we go any further into this tooth story, let’s do a quick review of Heithersay’s resorption classifications. 

  1. Class 1: A small, invasive resorptive lesion near the cervical area with shallow penetration into dentin.
  2. Class 2: A well-defined, invasive resorptive lesion that has penetrated close to the coronal pulp chamber but shows little or no extension into radicular dentin.
  3. Class 3: A deeper invasion of dentin by resorbing tissue, not only involving the coronal dentin but also extending at least to the coronal third of the root.
  4. Class 4: A large, invasive resorptive process that has extended beyond the coronal third of the root canal.

Since this resorption is approaching the pulpal wall, I would classify it as a Class 2 external cervical invasive defect. My strategy for root resorption treatment would be to perform surgery first, and then follow up with a root canal if there is a pulp exposure or other symptoms post-surgery. It’s really important to create the lingual seal in this case to keep bacteria out of the tooth following treatment. 

This is definitely a case where I’d love to work with my periodontist, since their skills in that area are better than mine. I’m never afraid to work with a team if it benefits my patients! 

Where the Tooth Story Goes from Here

I find that case acceptance can be SO challenging in situations like these, and this patient was no exception. Although I made her completely aware that she needed further treatment, one look at her face told me that she wasn’t ready to accept it at that time. I really feel for her!

What did I do? I put her on a call list for about two months after her treatment on Tooth #19. When that call happens, I’ll remind her that this external resorption treatment is necessary, and I will go over the details with her again. Having strong communication with your patient is half the battle.

I also included all the information in my report to the referring dentist in the hopes that they will also encourage the treatment plan. Ideally, the patient will want to move forward with treatment after she recovers from the root canal on Tooth #19. I would hate to see her lose these teeth due to progression of the resorption. The sooner we can start external resorption treatment, the easier it will be.   

So, what are the takeaways from this tooth story? First, root resorption treatment can be super tricky. But second, I hope this story also showed you how important it is to examine what’s happening not only on the problem tooth, but in the surrounding areas as well. Radiographs and CBCT can give us so much insight into what’s really causing a patient’s pain and symptoms if we’re willing to dig just a little deeper! 

What did you take away from this case? Let me know in the comments!