Failed Root Canal Symptoms
Oct 28

Failed Root Canal Symptoms - How much does it cost to fix it?

Oct 28

Dental conditions may be bad, but you know what’s the worst? A failed dental procedure. Yes, dental treatments can go wrong. While it’s rare, it does happen. 

A root canal is a common dental procedure that goes wrong if done incorrectly and requires immediate attention. The patient may start to notice failed root canal symptoms soon after the procedure.

When a tooth starts to decay or get damaged completely, it requires a root canal. Hence, the procedure is performed in order to remove the damaged nerve and clean the pulp. Millions of root canals are performed every year with a high success rate, and most patients leave the clinics satisfied. That said, not every dentist is experienced in performing root canals, and if such a dentist does the procedure, chances are high that it fails.

Failed Root Canal Described

A root canal is called failed when the procedure is not done correctly, leaving the infection intact. When such a thing happens, the treated tooth gets infected again and starts causing pain. There is no specific time period for a failed root canal to surface. It may take even years to know that the root canal went wrong. 

Also, when a root canal is done inaccurately, you will start having symptoms like gum swelling, pimples on the gums and tooth discoloration. Urgent treatment is required in such a case. Otherwise, the infection spreads to the other nearby teeth.

Why does a Root Canal Procedure Fail?

There could be many reasons a root canal procedure fails. Below we have listed the common mistakes dentists make while performing a root canal.

  • Poor Sanitation: For a successful operation, the dentist must keep their tools sterilized and clean the space where the procedure will take place. Also, they must stop the saliva from touching the treatment area to avoid complications.
  • Crack or fissure: While it may not sound like a serious issue, a minor crack in a tooth can cause a big problem after the treatment. A broken or cracked tooth has fragile roots that can be damaged after the treatment.
  • A missed nerve: When a dentist performs a root canal, he/she must cover the entire affected area; failure will leave some infection or nerve untreated, which may spread to other teeth.
  • Broken root tip: During the procedure, if the root tip breaks or gets separated, it begins to rot and turns into a serious problem. In a worst-case scenario, your tooth may necessitate getting extracted.
  • Soft Sealant: A failed root canal may be the reason for improper sealant application after the procedure. If it doesn’t get dry and harden instantly, it could let the bacteria enter the tooth again.
  • Crown breakdown: When a root canal is done, a dental crown is placed to protect the tooth from further damage. If, for any reason, the crown cracks or breaks, the bacteria will enter the tooth and cause infection. Therefore it is recommended to get the permanent restoration done after a root canal.

What are the Signs of a Failed Root Canal?

Once you get a root canal done, you must be extra careful about your oral health. If you begin experiencing pain, discharge, swelling or unusual boil on your gumline, make sure you seek professional advice. These are typically the signs of a failed root canal.

Delaying your visit to a dentist will result in serious complications. Whether your root canal was performed a month or several years ago, you may notice the signs of a root canal failure at any time. Just know that root canal pain is usually felt near the treated tooth. Sometimes you don’t feel pain, but your teeth become heat and cold-sensitive.

On the contrary, if the procedure has been done correctly, you will feel the pain vanishing with time. In fact, you will feel lighter and normal again in a few days.

Failed Root Canal Symptoms

Common Failed Root Canal Symptoms

Here are the common root canal failure symptoms you will encounter:

  • Pain in the treated tooth: One prominent symptom of a failed root canal is a pain in the treated tooth. If the procedure goes right, the pain will lessen with time. If the procedure fails, you will experience the same level of discomfort as before the root canal. And maybe an infection as well.
  • Swelling: When tooth infection occurs after a failed root canal, you experience swollen gums in nearby areas.
  • Discharge: Some people experience discharge from the infected tooth, indicating the likelihood of abscess formation.
  • Tooth Sensitivity: Normally, you should not feel sensitivity in the treated tooth after a root canal. However, you may have sensitivity issues if it goes wrong, especially when you eat/chew hot or cold food items.
  • Pimple on the jaw: Another common symptom of a failed root canal is the occurrence of boils/pimples on your gumline, which otherwise don’t appear in a normal case scenario.
  • Sinus Issues: This symptom is rare and typically experienced when the infection spreads to the back teeth linked to the sinuses. As a result, you have a runny nose, facial and jaw pain, stuffiness, bad breath and congestion.
  • Tooth Discoloration: A failed root canal can cause tooth discoloration or a change in tooth structure. If you notice anything like that, get it checked immediately.

So these were the common symptoms of a failed root canal. The most dangerous situation is when no symptoms appear after a root canal failure, and you find it out through a regular dental checkup. Therefore, getting a routine checkup from your dentist is always advisable.

Why do Dentists recommend Root Canals?

A root canal is a simple dental procedure done to save a damaged tooth from extraction. It must be performed when an infection inside the tooth leads to abscesses.

The pulp inside the tooth contains nerves, tissues, and blood vessels which help create stiff tissues around the tooth during its growth and development. That said, a fully matured tooth no longer requires pulp to survive and gets nourishment from surrounding tissues. When the tooth's nerves become infected, it causes excruciating pain and must require immediate treatment.

Following are the reasons why a root canal procedure may be necessary:

  • Large fillings
  • Faulty crown
  • Deep decay
  • Cracked tooth
  • Repeated procedures on the same tooth.

How is an accurate Root Canal done?

Typically a root canal is performed by a dentist or endodontist (a dentist who deals with the diagnosis, prevention and treatment of tooth pulp-related issues.) When a patient has a complicated dental pulp injury, the dentist may recommend consulting an endodontist. They may also perform a root canal if required. Following is the correct procedure for a root canal:

Step 1: In the first appointment, your dentist will take an X-ray of your root canal to figure out which area they need to work on as well as determine any infection in the surrounding bone.

Step 2: Typically, the dentist performs the procedure in the second appointment to give you time to prepare for the dental treatment. Before starting, the dentist will administer local anesthesia to numb the area. While you may not need anesthesia as the nerve is already dead, your dentist will give you one to make you feel relaxed.

Step 3: Next, the dentist will use a rubber sheet to keep the area dry from saliva.

Step 4: Now, the cleaning will take place. The dentist will drill a small area to access the pulp, decayed nerves and bacteria to remove them using a series of endodontic files and reamers. Once the cleaning is done, water or sodium hypochlorite will be applied to the treated area to remove debris.

Step 5: The next step involves sealing. While some dentists do it on the spot, others wait for the tooth to settle to seal it. If your tooth is cleaned out and the root canal has been held for another appointment, your dentist will place a temporary filling in the exterior hole to prevent food particles or saliva from entering.

Step 6: In the next appointment, a sealer paste and gutta-percha (a rubber compound) are placed to fill the interior of the tooth. Then a filling will be applied to close the access through which the root canal was done.

Step 7: The final step is optional. Since your tooth goes through so much after a root canal, it needs protection to get infected again. Therefore, dentists suggest getting a crown as a shield to protect the treated tooth. However, it will depend on the patient’s choice.


A failed root canal can be problematic. In fact, it may cost you even more than the initial procedure, depending on your case. Talk to your care provider regarding the procedure as well as your health insurance company to provide you with ways to finance the treatment. Get it right as soon as possible to prevent any further costly therapies.