Endodontic treatment can be challenging in many ways, especially when treatment is needed along with the molar teeth. For patients with complex tooth problems, endodontists need to look into and understand the tooth’s anatomy to access the channels, pulp, and blood vessels within the tooth to be able to treat it. However, one tooth apex is considered highly advanced to treat, and it’s called the MB2 canal. This canal, also known as the second mesiobuccal canal, can particularly frustrate endodontists when treating patients because of how difficult it can be to reach it.
When it comes to truly understanding why the MB2 canal is such a place of frustration and fascination for dentists, we need to consider how root canal treatments work with the tooth’s anatomy to access the apex and root channels that are being affected. In today’s article, we’re looking into the structures of the root canal system, specifically the MB2 canal, and give you some insight into the best techniques used to treat this difficult canal and improve the success of a procedure.
The Structure and History of the Infamous MB2 Canal
Throughout dentistry, our understanding of the canal system within teeth was extremely limited. Still, even before the development of the x-ray machine, many dentists were exploring these channels to understand the anatomy of our teeth better. It wasn’t until 1917 that Dr. Walter Hess discovered the MB2 canal. He discovered this canal alongside many others by using liquid rubber, allowing it to harden within the channels of the tooth, and them removing the rubber through a process called decalcification. When presented, the models showed the presence of this unusual canal, alongside many other identifiable systems that dentists could begin identifying and classifying these channels.
However, it wasn’t until 1969 that these canals were beginning to be classified into types. These types allowed dentists to understand the tooth’s anatomy better and improve education for future dentists. When it comes to the MB2 canal, we classify it as the maxillary first molar and the maxillary second molar. The first molar is the earliest permanent tooth that forms in the mouth, making it vulnerable to cavities. The MB2 canal within the first molar is difficult due to its complexity in structure and position within the canal system. It regularly develops within the first molar, as between 48% and 88% of people worldwide have the MB2 canal. The second molar has unusual root fusions for the second molar, as it can have in between one and five roots that are fused. This fusion rate exists between 5% and 42%, but the most common iteration found in people’s teeth is four root canal fusions, including the MB2 canal.
Both of these molars have a higher amount of predictability because many of the other molars and other teeth often develop unique fusions and root systems that are entirely unique to the patient. Because it’s so unique, many endodontists have to look at the person’s root canals to pay attention to the variations that occur and then provide more customized treatment.
Why Endodontists Need To Treat the MB2 Canal
Root canal treatments typically leave the MB2 canal out of the equation entirely due to its complexity and impact it has on the success of the treatment. Even while many patients often are able to get successful treatments without this focus, the MB2 canal can still present many dangers when it comes to preserving the integrity of the tooth. Experienced endodontists that have to perform complex procedures often have to look at the MB2 canal because this canal presents a high risk to procedures that involve intense removal of bacteria. If unsuccessful, it can result in returning pain for the patient, with a higher sensitivity to temperatures and a larger chance of becoming necrotic.
The sealing process performed during root canal treatments is typically part of the reason that endodontists don’t treat the MB2 canal. The sealing process typically allows bacteria within the tooth to die off, but the biggest risk that comes with this process is how the canals work through the blood vessels, pulp, and tissues to remove the bacteria. Often, the root canals within the teeth are able to communicate through processes called isthmuses and anastomoses. By using these processes to connect the tissues, canals, and blood vessels to the pulp, also makes it more likely for the bacteria to spread to the MB2 canal and cause reinfections.
How Endodontists Treat The MB2 Canal
Because of this risk of root canal failure, if the MB2 canal is infected, then the MB2 canal needs to be treated. With the development of CBCT technology, it’s now become a lot easier to access this canal and remove bacteria from the maxillary molars. Endodontists often need to focus on treating the entire root canal system to flush out the infection and bacteria completely, and for treating the MB2 canal, they go through the following steps:
- Diagnosis: CBCT technology, or cone-beam tomography systems, help to capture as much data as possible to look inside the tooth and observe any abnormalities within the root canal system. In these cases, the endodontist would be observing either the maxillary first or second molar to diagnose the type of endodontic pain properly.
- Finding the MB2 Canal: For experienced endodontists, they would need to look for the MB2 canal by observing the fissures and grooves alongside the adjacent root canals.
- Focus On The Surrounding Canals: Any of the surrounding canals that may be infected, necrotic, or calcified need to be addressed before accessing the MB2 canal.
- Treating the MB2 Canal: Once all of the adjacent canals have been treated for infection or decay, then the MB2 canal can be treated, instrumenting the tools through the proper grooves and thoroughly clean it completely before sealing.
Ultimately, the MB2 canal presents many complex systems, but it’s essential that the MB2 canal should be paid more attention to when performing root canal treatments to help reduce the failure rate and protect patient’s teeth.
