Reasons for Failures and Symptoms of a Failed Root Canal
Is it possible for a root canal procedure to be unsuccessful? There are various factors that might contribute to a negative result.
Not all root canal treatments result in successful outcomes, as indicated by published studies reporting success rates ranging from 53% to 95%. Various factors contribute to the range of outcomes observed. The reporting of endodontic success and failure depends on several critical factors, including the frequency of follow-up evaluations, the skill of the provider, the selection of the tooth for treatment, the number of cases reviewed, the patient's subjective response to and compliance with treatment, the criteria used to determine failure, and the interpretation of results.
There are more than 20 reasons reported in the literature that may influence the outcome of conventional endodontic therapy. Through the literature, these factors have been evaluated and reviewed, with both acceptance and denial as to their influence on endodontic success rates.
There are some factors, however, that are regularly described to have an influence on success or failure. These factors are as follows: the extension of the filling material, quality of the obturation, case selection, root canal system anatomy, deficiency of cleaning and shaping, the existence of periapical pathosis, iatrogenic procedural errors, and length of the observation period.
Nowadays, the strongest belief is that the most important cause of failure is recontamination of the entire root canal, resulting from coronal bacterial leakage.
Preventing Coronal Leakage
At PreserveYourTeeth Dentistry, we take several measures to prevent coronal leakage, which is crucial for the long-term success of root canal treatments.
First and foremost, we work with rubber dams (RAM) to ensure complete isolation and control of the operating field. This isolation helps prevent saliva and bacteria from contaminating the treated area.
We also use lasers to clear any remaining bacteria from the coronal side of the tooth. This step ensures a cleaner and more sterile environment, reducing the risk of recontamination.
To further strengthen the area between the roots and the crown of the tooth, we use bonded fiber core posts. Meticulous bonding of these posts helps prevent coronal leakage by providing a secure seal and additional structural support.
It's important to note that after a root canal, the tooth can become brittle and more prone to fractures, particularly in the root area. Therefore, placing a well-made crown that is properly sealed to the tooth is also essential for the long-term success and durability of the tooth.
Technological advancements in dentistry and specifically endodontics have vastly improved the quality of care provided to patients. These advancements allow clinicians to gain insight into the re-treatment of failing root canals. In many cases of infection or symptom recurrence, a second root canal treatment (root canal re-treatment) is considered. Due to training, practice, and patience, clinicians can expand their capabilities alongside these technological advancements to perform endodontic retreatments with increased success.
How Can You Recognize the Symptoms of a Failed Root Canal?
A root canal treatment is not a very pleasant dental procedure and when it goes wrong, the problem becomes even worse, but you may be wondering, besides having a toothache, how can you know your root canal treatment has failed? Here we will mention some symptoms that may indicate your tooth may be in need of a root canal re-treatment.
Persistent pain after endodontic treatment is one of the most common symptoms you may consider; when fully recovered from the root canal procedure itself, the tooth should not remain sensitive. Feeling pain when you apply pressure is not a good sign and it may mean there is something wrong with your root canal.
Sensitivity itself is also another symptom to be mentioned. Since the main objective of a root canal is to remove all nerves from the tooth, you should not be feeling anything at all. If you do feel sensitivity to hot or cold in that specific tooth, it means that a nerve has been missed. It is definitely an indicator to review.
On the other hand, it is important to consider that discoloration is not necessarily a sign of a failed root canal; when your dentist drills into your teeth, all the nerves are being removed and there will normally be a little bit of bleeding. This blood will then seep into the filler that your dentist uses to fill the tooth. As you probably know, blood turns brown when it dries. This is why tooth discoloration is somewhat normal after a root canal treatment.
It should be noted that this is not a complete list of symptoms. However, the most common symptoms were covered in this blog. You should also consider that consultation with the appropriate specialist, or team of specialists, to determine the feasibility of treatment is very important for the clinician when assessing a root canal that has failed, since many of these symptoms can be due to other problems, and have nothing to do with your root canal.
At PreserveYourTeeth Dentistry, we believe in early diagnosis and prevention. We assess our patients’ oral hygiene at every visit and conduct a very thorough examination to evaluate a tooth’s vitality, which may determine the next steps to be taken and help us decide the best treatment for each specific case.