Root canal treatment is one of the most reliable dental procedures that can help alleviate pain and save a decaying tooth.
When performed correctly, the success rates are high. However, there are some mistakes during the Root Canal Treatment process that can compromise the outcome. (Which I am also guilty of making)
The Burning Question about Root Canal Treatments
So the question that often comes to mind is: why do root canals fail? Oftentimes, certain root canal mistakes, whether they are technical or procedural, allow bacteria to re-enter and thrive leading to pain and infection.
In this article, we will cover the 10 most common endodontic errors, their consequences, and, most importantly, how to prevent them.
Inadequate Diagnosis
Unfortunately, many patients delay the need to get a treatment which usually makes the diagnosis inadequate and inefficient. When it comes to the dentist, failure to recognize complex anatomy often leads to incomplete treatment.
The major mistake can be relying on a single X-ray or even ignoring patient history. Some cases, such as vertical root fractures or advanced periodontal disease, may not be suitable for RCT at all.
To avoid it;
- Multiple periapical radiographs should be taken from different angles including CBCT scans when possible.
- Both the pulp and periapical status should be carefully evaluated.
Under-Preparation of Access Cavity
A poorly made access cavity is similar to working in a dimly lit room. It limits the visibility and allows the risk of missed canals. The creation of small or misaligned openings restrict the straight line access that allows less complications.
To avoid it;
- Principles of conservative but strategic access should be followed.
- The use of magnification and illumination to improve visibility.
A well-prepared cavity provides better control over instrumentation and reduces procedural errors.
Missed Canals
Missed canals are probably the most common cause of retreatment. Some teeth have additional canals that are difficult to detect. For example, a lower incisor, which typically has one canal, may contain a second, hidden canal.
If the dentist ends up missing it, there might be an infected tissue left behind that would cause problems in the future.
To avoid it;
- Always explore the infected area carefully with endodontic explorers. Use ultrasonic tips, magnification, and CBCT imaging.
- Knowledge of root canal anatomy variations is essential for avoiding this error.
- Over Instrumentation
It is crucial that the instrumentation should be precise. Extending beyond the apex or creating ledges within the canal can damage periapical tissues and make proper obturation nearly impossible.
To avoid it;
- Determine the accurate working length using both radiographs and apex locators.
- Avoid aggressive filing. Careful technique and advanced training help prevent ledges.
For background study, visit the American Association of Endodontics and discover how root canals work.
Insufficient Irrigation
It is not just the mechanical shaping that matters when it comes to a root canal procedure. When cleaning, all the bacteria and debris should be flushed out. Skipping the proper irrigation process guarantees problems.
To avoid it;
- A rubber dam should be used. This barrier isolates the tooth from saliva, which contains millions of bacteria that can contaminate the root canal.
- Incorporate sodium hypochlorite (NaOCl) generously, along with EDTA to remove the smear layer.
- Activate solutions with sonic or ultrasonic devices to improve penetration.
Poor Obturation (Overfilling or Underfilling)
After the canal has been properly cleaned, the dentist must fill and seal all the space completely. Any gaps, voids, or extrusion beyond the apex can cause reinfection.Thus the filling material should be tightly packed to prevent bacteria from re-entering the root system.
To avoid it;
- Master obturation techniques like lateral or vertical condensation.
- Always check your fills radiographically and re-do if results are questionable.
Ignoring the Coronal Seal
Even if the canal has been perfectly cleaned and filled, failure is inevitable if the coronal seal is weak. If the temporary or permanent restoration fails to create a strong seal, bacteria can penetrate the tooth and cause reinfection.
To avoid it;
- Place well-sealed temporaries immediately, and restore with a crown or permanent filling as soon as possible.
- A crown covers and protects the tooth while ensuring a tight seal. Timing also matters as delaying the final restoration increases the risk of contamination.
- Remember the coronal seal is as important as the root canal itself.
Instrument Separation
Rotary files and hand instruments are prone to fatigue. A fractured instrument inside the canal can block cleaning and compromise treatment. The major mistake that is committed is reusing too many files or applying excessive force.
To avoid it;
- The instruments must be inspected regularly and worn out files must be discarded immediately.
- A proper use of torque settings on rotary devices should be implemented.
Lack of Follow-Up
Even after a successful procedure, monitoring is vital. Many cases of root canal failure are discovered late because patients don’t return for recalls.
Mostly, patients believe that once the infected pulp is removed, they no longer need to care for the treated tooth or come in for a check up.
To avoid it;
- Schedule regular dental check-ups that will allow your dentist to monitor the treated tooth and ensure its long-term success.
- Have radiographs at 6–12 months. Early detection of periapical pathology allows for intervention before symptoms appear.
Poor Patient Compliance
In some cases, the dentist does everything correct, and the procedure is a success too. Nevertheless, the patient doesn’t follow through. Skipping crown placement or neglecting oral hygiene leaves teeth vulnerable.
To avoid it;
- Educate the patients about the importance of prevention and post care.
- Inculcate the need of final restorations and checkups since a well informed patient is less likely to skip such vital steps.
How to Prevent Root Canal Complications
Mistakes as a human being are inevitable. However, one must know that prevention is always better than a cure. Here is a quick checklist that would aid you in keeping yourself within the safe zone!
- Conduct proper diagnosis.
- Create proper access and locate every canal.
- Avoid ledges and over instrumentation.
- Clean properly and activate solutions.
- Aim for a void-free obturation.
- Never underestimate the value of a tight coronal seal.
- Follow up regularly and reinforce patient education.
Final Thoughts!
As you can see, the common causes of root canal treatment failure aren’t mysterious.They are simply errors in technique or oversight.
By recognizing these common endodontic errors, dentists can refine their approach and ensure long-term success.
As for the patients, it’s imperative that they listen to their doctor as awareness is equally needed. If you’ve had a failed root canal treatment, it doesn’t always mean extraction is the only option. Hopefully, a retreatment or specialist care can often save the tooth.
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