Y’all, I have a new article on the Dentistry Today website, and I mean business with this one! Titled “The Endodontics Renaissance and Modern-Day Root Canals,” I really take aim at creating awareness for the possibilities root canals can have toward fixing tooth pain. A big part of this Dentistry Today feature my analysis of the relationship between tooth anatomy and endodontic technology.

Through breaking down four different case studies, I want to show you how conquerable some scary situations might be, and give you the confidence to tackle them yourself. Through understanding these techniques, you’ll come to realize the ROI on a financial and clinical level is too good to ignore.

Let me give you a taste of the first case.


Case 1

This first case will help clarify my intent here. When you examine the radiograph of tooth No. 19, it appears that the root canal has been done correctly. There were 4 canals found. They were densely filled, yet there was still a periapical radiolucency. What do you see that could be a potential reason for the failure? Let’s start with a diagnosis. This tooth was tender to percussion, obviously had no response to cold, and all probings were within normal limits. The diagnosis was previously treated and symptomatic apical periodontitis of tooth No. 19 (Figures 1 to 3).

Taking a closer look, the obturations were a few millimeters short. This is a definite source of bacteria, and we had to question the patency in this case. Most practitioners will look at the “J-shaped” radiolucency around the mesial root. Based on what we were taught in dental school, it is the textbook definition of a cracked tooth. There are studies showing that the mesial root of the mandibular first molar is one of the most common roots to fracture. So is it reinfected, or is this tooth fractured?

dentistry today feature

In the first step, removing the gutta-percha, I started to look around the tooth. One of the things I do in every mandibular molar is trough the groove between the MB and the ML canals. Once that was done, note what was found while using the microscope (Figure 4): a middle mesial canal! No wonder there was a lesion around the mesial root. There was still original bacteria in that canal that could explain the radiolucency around that root! Did you know that the middle mesial canal is present anywhere from 2% to 18% of the time? My recommendation is to look for it in every single mandibular molar (Figures 5 and 6). Pro tip: Using high magnification will make your life much easier. Going back to the CBCT to see if I could see the canal with my cone beam, I wondered if I had missed it during my initial workup. You can see from both the axial and the coronal views that there is really no sign of a middle mesial canal.

This case shows that CBCT scans may not always provide this information; you still have to use all of your diagnostic skills and “tools” (Figures 7 to 9). Luckily, you can see this middle mesial canal with a microscope in this case, but you have to understand that such a thing exists in the first place. Without it, and not being aware of this anomaly, the same 4 canals would have been re-treated, ending up with the same outcome—a failed root canal. The point is that there are several cases in which you can see those extra canals. It’s just that some canals are too small to be seen clearly by imaging alone, so in endo, you have to marry all of the technologies together.


Don’t get me wrong, I know that what I’m telling you to do can take some practice. Some trial and error. But it’s worth it in the long run, trust me!

And if you enjoyed reading about that case in the Dentistry Today feature, well there’s three more that are just as juicy at the link below! Go check them out and let me know your thoughts!

The Endodontics Renaissance and Modern-Day Root Canals

Empower yourself,


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