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Failed Root Canal Symptoms & Detection

Editor: Saeideh Mahmoudi
Date: July 20, 2025

What Is a Failed Root Canal?

A failed root canal can make you worry if you keep feeling pain, swelling, or sensitivity that won’t go away. When this happens, it’s crucial to get the right diagnosis and treatment from a specialist who knows what they’re doing. Dr. Alavy at Hemlock Dental Clinic is an expert at spotting and fixing root canals that have gone wrong. She aims to save your tooth when she can and make you feel better. If you think you have faced a failed root canal, give our office a call at 604-738-9202 today. Book a check-up with Dr. Alavy to get a clear idea of what to do next.

What Are the Symptoms of a Failed Root Canal?

Recognizing the symptoms early can help you avoid complications. Common signs of a failed root canal include:

Persistent pain or pressure near the treated tooth
Swelling or tenderness in the gums
A visible pimple or bump on the gum
Discoloration of the tooth
Sensitivity to hot or cold
Bad taste or odor in the mouth

If you’re experiencing any of these symptoms, visit a walk-in dental clinic in Vancouver or consult with Dr. Alavi at our general dentistry clinic as soon as possible.

Not all discomfort means failure—sometimes it’s part of the normal root canal recovery time.

Why Do Root Canals Fail?

Root canal failure can be caused by multiple factors:

Missed or untreated canals
Complicated root canal anatomy
Cracks or fractures in the tooth
Delayed or poor placement of the crown
New decay or trauma

Good Root Canal After Care can lower the risk of reinfection—avoid smoking, keep the area clean, and follow your dentist’s instructions.

What Happens Next When a Root Canal Fails?

When a root canal fails, there are several treatment options available depending on the severity of the issue:

Condition	Possible Next Steps
Mild discomfort or tenderness	Monitoring, pain management
Infection or abscess	Endodontic retreatment
Structural damage (e.g., crack)	Tooth extraction and replacement (e.g., dental implant)

Learn more about endodontic retreatment here.

Close-up of a dental tool used during root canal treatment, illustrating the precision required to prevent root canal failure. Missed canals, poor sealing, or bacterial contamination can all lead to complications. — Close-up of a dental tool used during root canal therapy, highlighting the importance of precision in preventing treatment failure. In the context of Failed Root Canal Symptoms & Detection, improper cleaning or sealing can lead to reinfection and complications.

What Is the Root Canal Failure Rate?

According to studies, root canal treatment has a high success rate—about 85% to 97%. However, failure can still occur. That’s why regular checkups with an endodontist in Vancouver are crucial.

What Causes Root Canals to Fail?

A failed root canal can happen when bacteria are able to re‑enter or remain inside the tooth. This typically occurs because of one or more of these reasons:
1. Not cleaning or sealing the canals
2. Bacteria getting back in through gaps around the crown or filling
3. Fresh bacterial infection from tooth decay or cracks
4. Lack of good oral care or skipping check-ups after the procedure

Is It Possible to Repair a Failed Root Canal?

In many cases, a failed root canal can be successfully treated and the tooth can still be saved. The most common approach is endodontic retreatment, where the dentist removes the old filling material, thoroughly cleans and disinfects the canals again, and then seals them carefully. Other treatment options may include:

Apicoectomy (surgically removing the tip of the root and sealing it).
Extraction followed by dental implant placement, if the tooth is too damaged to be restored.

Can You See a Failed Root Canal on an X-ray?

Yes. An experienced dentist or endodontist in Vancouver can often identify issues such as dark spots near the root tip, indicating infection or bone loss.

Should the Dentist Pay for a Failed Root Canal?

Responsibility depends on the cause. If the failure is due to negligence or improper technique, the dentist may offer retreatment at a reduced cost or for free. However, many failures occur due to unpredictable biological factors.

Can a Root Canal Become Infected Again?

Yes. Even after a successful treatment, reinfection is possible if bacteria re-enter the tooth. That’s why aftercare and follow-up visits at a reliable general dentistry clinic are essential.

Patient Story: Roman’s First Root Canal Experience

When Roman arrived at Hemlock Dental, he wasn’t expecting to need a root canal. What began as a broken tooth from eating a pomegranate quickly turned into something more serious. After a thorough examination, Dr. Alavi and the team discovered underlying cavities that had gone unnoticed — a reminder of how important regular dental checkups are.

Despite it being his first root canal, Roman felt well cared for throughout the process. The supportive and experienced staff helped ease any anxiety, and the treatment successfully saved his natural tooth. Roman left the clinic impressed by the professionalism of the team and grateful for their skillful care.

Today, Roman is pain-free — and much more mindful about his oral health. His story is a reassuring example that even unexpected dental issues can be resolved with the right team and timely treatment.

Screenshot of a 5-star Google review from Roman, who shares his positive experience at Hemlock Dental Clinic after receiving his first root canal. The review emphasizes the importance of dental checkups and the professionalism of Dr. Alavi’s team. — Google review showing a patient’s successful treatment after experiencing Failed Root Canal Symptoms & Detection. Roman’s story at Hemlock Dental emphasizes the importance of timely diagnosis and expert care in saving a tooth.

Root Canal or Pull Tooth?

Not sure whether to save or extract the tooth? Here’s a quick comparison:

Option	Pros	Cons
Root Canal	Preserves natural tooth, less invasive	May require retreatment
Tooth Extraction	Removes infection completely	May need implant or bridge later

If you’re concerned about failed root canal, it’s important not to ignore any ongoing pain, swelling, or other changes around the treated tooth. A failed root canal can often be fixed with advanced treatments, especially if it’s recognized early by a skilled dentist. At Hemlock Dental in Vancouver, Dr. Alavi and the team carefully look at your symptoms, check X-rays, and explain whether retreatment, apicoectomy, or replacement is the best choice for your long-term dental health. If you’re still feeling uncomfortable or think your root canal didn’t succeed, call Hemlock Dental today at 604-738-9202 to arrange an evaluation and get a clear, personalized plan for your treatment.