Steps of root canal treatment

Although root canal treatments are sometimes feared by patients, they are not painful. You can rely on the expertise, empathy and experience of our root canal experts like Dr Mosahebi and our founder, Prof Christian Mehl.

Step-by-step root canal process

  • Our endodontists start by identifying the affected tooth. 
  • Before treatment begins, your dentist is likely to take a number of additional measurements (or in some instances, X-rays) of the affected tooth so that they assess the extent of the damage. 
  • After anaesthetising the tooth and the surrounding area your dentist may then place a rubber-like material around the affected tooth (known as a ‘dental dam’) to keep the area dry during treatment. This prevents saliva and bacteria from contaminating the area and stops material and liquids from the treatment entering your mouth.
  • The access to the damaged nerve is achieved by drilling a small hole into the chewing surface of the tooth.
  • The length of the root canal is measured using an electronic gauge in a process known as endometrics, this also helps reduce the necessity for additional X-rays. 
  • The root canal is cleaned using rotating files and a tailor-made combination of disinfectants until the root tips, known as the apices, are reached.
  • Following preparatory treatment your dentist will sometimes clean the nerve canals a second time by using a specially developed file (SAF system). This step is aimed at killing bacteria and removing tissue remnants in the infected tooth.
  • After a member of our dental team has conscientiously and carefully prepared and disinfected the root canal, we seal it with a thick root filling to prevent bacteria entering. The material we use for this, gutta-percha, has proven to be very reliable. Feel free to ask our endodontics team about gutta-percha and its advantages over other alternatives.
  • For back teeth, crowns or partial crowns are used after this root canal treatment to prevent tooth fractures or reinfection. The restoration stabilises the tooth in such a way that it will be twice as strong as a natural tooth free from decay.
  • Depending on the severity of the inflammation and the complexity of the patient’s root canal system, most treatments of this nature require only one visit to the dentist.
  • You may suffer from some swelling and discomfort once the anaesthesia has faded. Your dentist may recommend over-the-counter pain relief to help manage this discomfort over the next few days.

Root canal for nervous patients

Patients who are particularly worried about root canal treatment can undergo this dental treatment under light or deep sedation if they would prefer not to experience the entire dental procedure under just local anaesthesia.

Root canal treatment is often a long procedure and as such many patients dread having to spend too much time sat in a chair. To help avert boredom and help distract you during the root canal procedure, we provide video glasses so you can relax and watch a film or television show of your choice.

How does tooth ache develop?

Have confidence in our root canal treatment undertaken by an endodontic specialist

An example of a root canal treatment in pictures


Root canal is a common dental procedure that is usually undertaken by a general dentist, though we’re proud to offer the skill and experience of expert root canal dentists like Dr Mosahebi or Prof Mehl. Our specialists have not only completed thousands of root canal procedures, but they also regularly publish scientific research and lecture about the subject, such is their reputation and expertise.

A temporary filling might be necessary if your root canal procedure requires two or more appointments. After the pulp chamber has been cleaned, your dentist might place a temporary filling until your next appointment.

Endodontics refers to the diagnosis and treatment of pain relating to teeth. Expert endodontists, like Dr Mosahebi or Prof Christian Mehl, are highly trained general dentists who are also experienced in endodontic therapy like root canal and apicectomy. Dentists can only qualify as endodontic specialists following additional training at dental school. It’s common for endodontists to also be heavily experienced using the latest digital dentistry technology like 3D scans which help them improve accuracy and effectiveness in surgery.

Root canal has a poor reputation amongst dental patients for famously not being “pain-free”. Root canal is a necessary dental intervention to ensure that the problem isn’t further exacerbated without treatment and avoid turning into a problematic infection.

Most patients do experience some discomfort, pain and swelling following the root canal procedure. During the procedure itself, the anaesthesia is strong enough to numb the area so that you won’t feel any pain.

In the days following the endodontic treatment, over-the-counter pain relief may be used to help manage pain and discomfort levels. If you experience severe pain following root canal, please inform your dentist straight away in case you require re-treatment.

Root canal treatment costs differ depending on the treatment and the oral health of the patient. Costs start at £120 for a review (including x-ray) going up to £1,400 for molar re-treatment. Emergency root canal treatment costs £250 and is offered to new and old patients alike. See our dental fees page for all of our indicative costs.

Toothache can happen because of one or more of the following:

  • tooth decay
  • trauma from an impact
  • cracks in the tooth
  • loose fillings or dental crowns
  • differences in pressure (e.g. when flying or diving)
  • chemical or thermal stimuli (hot and cold).

In rare cases toothache lasting for a week or two may be the result of a cold. Toothache caused by colds or changes in pressure initially only need to be observed. If needed we can cover sensitive tooth necks with small fillings. Root canal treatment should only be undergone when the tooth that is the source of the pain has been identified conclusively.

When the inflammation of the dental nerve in the pulp chamber (pulpitis) leads to uncontrolled dying off of the nerve, this inflammation may spread to the surrounding tissue and bone. Endodontists can see this in an X-ray — it usually shows as a dark spot at the tip of the root. This is because minerals such as calcium and magnesium are released from the bone as a result of the inflammation. In the more advanced stages of this condition the inflammation might break through the bone and an abscess could form. In this stage patients tend to suffer severe root canal pain.

If the abscess empties through the membrane around the bone (the periosteum) and the gums into the oral cavity, this results in what is referred to as a dental fistula, at which point the pain stops. Once the inflammation reaches chronic stages dental cysts can form, which in most cases do not cause pain. However the tooth affected should be treated to prevent inflammation spreading.

Dental trauma is most common among children and young people. Falling off a bicycle, slipping and tripping up by the swimming pool or an impact from a hard object are among the most common causes. If a piece of the tooth breaks off or the tooth is knocked out altogether it is best to immediately see an endodontist. The tooth should be kept in a specially designed tooth rescue box, in saliva or in UHT milk.

If the tooth can be treated your endodontist has three choices:

  • If only part of the tooth is broken off without the dental nerve being affected, the fragment can be glued back on (which is why you should aim to keep the broken bit of the tooth safe!). Alternatively, the missing part of the tooth can be replaced using a filling or a veneer. Vitality of the tooth should be checked over the coming years.
  • If a large chunk of the tooth has broken off and the dental nerve has been exposed, the endodontist will first of all perform root canal treatment using a rubber dam. Depending on where the tooth is in terms of its growth stage, procedures may differ. In the early stages it may be possible to preserve the life of the tooth and to promote the natural conclusion of the growth of the dental root. The missing fragment can then be glued back on or the tooth can be sealed with a filling, a veneer or a crown.
  • If the tooth has been knocked out and stored correctly it can be put back in place. In this case, too, an endodontist must first of all perform root canal treatment. This is because the dental nerve was most likely torn off as a result of the trauma, and the dental nerve may have died. The tooth will then, for a duration of three months, be aligned with the teeth on either side.
  • If the tooth is lost, don’t despair an immediate implant might be the treatment of choice to solve your problem quickly.
Root canal treatment fees

Front tooth

from £600
Premolarfrom £900
Molarfrom £1,200
Emergency root canal treatment£250
Front tooth retreatmentfrom £800
Premolar retreatmentfrom £1,100
Molar retreatmentfrom £1,400
Review X-ray£120
Medication change£100

Contact us to find out about safe, pain-free & effective root canal treatment

Book an appointment with our specialist endodontic team today. Appointments are available at our central London dental clinic on the prestigious Wimpole Street.

Take confidence in the fact that we have dentists like Dr Mosahebi and Prof. Christian Mehl whose expertise diagnosing and treatment of root canal issues. We create a calm and stress-free atmosphere in our clinic to help relax and make nervous patients comfortable and confident.