Root canal treatment is supposed to provide solutions to your dental problems. Unfortunately, a root canal is not always foolproof. Some of the causes of a failed root canal are a failure to clean the root canal and bacteria buildup, breaks, and cracks in the dental crown, and erosion of the inner seal. In these cases, you will experience symptoms that your root canal is failing months or even years after the procedure. Here are some of the signs that you should watch out for:


Experiencing pain is normal immediately after the root canal procedure. However, if the pain lingers longer than usual or it's on-and-off for an extended period of time, it might be a sign of bacteria buildup or the presence of bacteria in the root canal. Your dentist will conduct further diagnostic test to determine why pain persists because it may be caused by other trigger factors.

Sensitivity to Pressure

Another sign of a failed root canal is sensitivity to pressure. Sources of pressure — such as biting or closing teeth and dental implants together — can cause pain ranging from slight discomfort to numbing pain. Typically, pain triggered by pressure means inflammation in the tissues surrounding the roots of the teeth.

Sensitivity to Heat

Sensitivity to heat is another sign of a failed root canal treatment. In fact, endodontic use thermal testing as a procedure for identifying failed endodontic treatments. They also prefer thermal testing over cold testing to determine which tooth is the culprit for the symptoms felt by the patient. More often than not, high sensitivity to heat means the presence of missed or unfilled root canals.

Swelling and Discharges

Swelling and discharges, which you might have experienced before and which might be the reasons why you have undergone root canal treatment in the first place, might be signs of failed procedure too. Typically, there are also boils inside the mouth which are called the fistulous tract. These gum boils are located at the top of the tooth's root. The tissue around these lesions could also be tender and discharge pus. Facial swelling is a severe symptom. Don't wait for severe swelling to occur. Go back to your endodontist as soon as you see boils in this region.

In case of root canal treatment failure, the next step will be either endodontic retreatment or extraction and dental implant. For retreatment, it is best to get the dental services of an endodontist with root canal specialization. For extraction, it is best to put replacement or dental implant to avoid the complications brought about by missing teeth.