Root Canal Treatment Side Effects, Risks and Complications

Root canal treatment is an extremely common and predictable procedure for our highly experienced and specialist endodontist at our 5* rated Hampstead clinic. When performed by a highly qualified and experienced root canal specialist, success rates for this procedure are extremely high.

But, as with any medical or dental procedure, you should always consider the potential complications, risks and root canal treatment side effects as detailed below.

Our highly trained specialist staff have been carrying out procedures like this for years and are able to greatly reduce many potential risks with careful planning.

Root canal risks – Colour changes

Dental pulp is the living part inside each of your teeth. If this becomes infected, however, it must be removed by root canal therapy. Whilst this saves your tooth from extraction, removes the infected tissue and stops the infection from spreading, it also means this living part is taken away.

Tooth pulp contains connective tissue, blood vessels and nerves, and without it, some patients can experience some form of discolouration in the treated tooth.

This is because, once the pulp is removed, the tooth essentially dies. In some cases, the dead roots of the tooth begin to start showing through the dentin. This only occurs in a very small percentage of cases though.

However, if this does happen, it can easily be aesthetically treated with crowns or veneers to improve their appearance.

Root canal risks – Sinus congestion

Everything within your body is connected to one another and your teeth are no different. A fairly common risk with root canals is that they can cause problems with your sinuses.

This is because, in some circumstances, liquid in your jaw can leak slightly through the membranes in your nose. It may not sound pleasant but because your root canal and sinus cavity are practically neighbours, it could potentially happen.

Whilst this is in no way life threatening, inflammation in the sinus cavities can be irritating with headaches and congestion being the main symptoms.

One way to check if your sinus problems are actually being caused by your root canal procedure will be a continuously salty flavour in your mouth.

In most cases, this problem goes away after a few weeks. If it persists, visit your dentist at Dental Perfection’s North London practice in Hampstead, or speak to your doctor about antibiotics or nasal saline solutions.

Root canal risks – Reinfection

This is the biggest worry many root canal patients have before their treatment. Of course, if you are going through a dental procedure to remove the infection, you want to know it was worthwhile.

Whilst reinfection is a root canal risk, your endodontist will go through a number of steps to stop this from happening.

Reinfection can happen if any stage of the root canal treatment is completed incorrectly. Before using fillers, your dentist will clean and disinfect the empty root canals. However, these are made up of many narrow, winding branches.

If not carried out by a specialist endodontist, it’s possible some of these passageways could be overlooked or inaccessible.

But, the most common root canal risk is a seal failure. Once your root canal is finished, your endodontist will need to reseal the access hole they used for the procedure. Any cracks or gaps in the seal will allow bacteria to re-enter the tooth.

It is also possible for a seal to erode. Permanent fillings or crowns will be used to close off the outer part of the tooth. Though these are designed to withstand pressure, without the proper care, these can wear down over time and allow bacteria to repopulate.

Root canal risks – Tooth cracking

Root canal treated teeth will never be as strong as they were before the bacterial infection and treatment. As the tooth essentially dies during the procedure, with all the living parts taken out, teeth can potentially become quite brittle.

That’s because one of the main functions of the dental pulp is to keep the tooth nourished and moisturised. This is why crowns are usually recommended post root canal to strengthen the outer area of the tooth again.

Root canal risks – Other complications

In an extremely small percentage of patients, the surrounding nerves around the affected tooth can be disrupted by the root canal procedure. In some cases, this can cause numbness in that area. This is nothing to worry about - it usually goes away within a few weeks.

Another root canal risk is an allergy to anaesthesia. If you have experienced an allergic reaction to anaesthetic during a previous medical procedure, inform your dentist immediately.

The long-term side effects of root canal treatment

The long-term side effects of root canal treatment are generally mild and rare. However, some people may experience the following:

  • Tooth fracture. The tooth may become more brittle after a root canal, as some of the tooth structure is removed during the procedure. This makes the tooth more likely to fracture, especially if it is subjected to heavy chewing forces.

  • Reinfection. In rare cases, the bacteria that caused the original infection may return and cause the tooth to become reinfected. This can lead to pain, swelling, and other symptoms.

  • Allergic reaction. Some people may be allergic to the materials used in root canal treatment, such as the filling material or the antibiotic used to treat the infection. This can cause symptoms such as swelling, hives, and difficulty breathing.

  • Nerve damage. In rare cases, the root canal treatment may damage the nerves in the tooth or surrounding area. This can cause pain, numbness, or tingling.

It is important to note that these are just the long-term side effects of root canal treatment.

If you are considering a root canal, it is important to talk to your dentist about the risks and benefits so that you can make an informed decision.

How to minimise risks from root canal treatment

For highly qualified specialist endodontists, like Dental Perfection’s Dr Shahrzad Rahbaran (GDC No. 68475), who has over 30 years experience, root canal treatment is an extremely common procedure. That means they’re able to mitigate many of these root canal risks with a skilled team and careful planning.

Before your procedure, you’ll have the chance to speak to your dentist about any potential complications that could occur during or after your treatment. Then, if anything were to happen, you can always come back to the Dental Perfection’s root canal clinic in Hampstead to speak to the experts.

And remember – prevention is always better than a cure, so ensure you maintain good oral hygiene following treatment, and that you avoid sugary foods and smoking.

Stay aware of the potential root canal risks and alert a dental or medical professional if you believe there is something wrong.

Example root canal treatment before and after

A step by step guide to root canal treatment


Root canal treatment consultation

We have talked about the risks of root canal treatment but you can also read about the many benefits to root canal treatment. To help you decide about going ahead with treatment you can find out more about the costs of root canal treatment.

To book your root canal consultation, or if you have any other questions, call us on 020 7431 2710, or come in see us at Dental Perfection’s North London clinic in Hampstead.

We have been working with clients from all over North London (including St Johns Wood, Belsize Park, Highgate, and Swiss Cottage) from our Hampstead clinic since 1979.

Our root canal clinic is less than a minute's walk away from Hampstead Underground Station.


See inside our state-of-the-art London root canal clinic

low cost	private London Endodontist Dr Rahbaran

Your specialist root canal dentist (Endodontist)

If you need expert root canal treatment from a friendly and highly experienced root canal dentist in London, our specialist endodontist, Dr Shahrzad Rahbaran (GDC No: 68475) can help.

Research has found that root canal surgery enjoys much higher success rates when carried out by a specialist endodontist.

Dr Rahbaran has over 30 years of dentistry experience and provides a full range of endodontic root canal treatments and is highly experienced at dealing with nervous patients.

Patients can even enjoy a movie or two, listen to music while treatment is carried out and if this doesn't help relax them, sedation can be offered.

5 star Google review rating

Root canal treatment review via Google Business

"Dear Dr. Sanei and Dr. Rahbaran - you are the best dentists in the world! You have converted me completely from hating going to see the dentist to looking forward to it!! That's just beyond magic. You have explained every single procedure during the surgery and treatment I felt so well looked after in your clinic.

Your skills and knowledge is fantastic. I cannot thank you both enough. I recommend you to every family member of mine and please keep on doing what you do - it is a truly life changing experience :)

I would also like to thank Debra and Stephanie and Lisa you ladies are so awesome and it's a pleasure to be your patient!! I cannot recommend this clinic enough!"
5 star Google review rating
Bailu Lu

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