Root Canal Treatments - Investigations

Authored by Dr Ben Williams, 09 Jul 2017

Reviewed by:
Dr Hayley Willacy, 09 Jul 2017

To confirm whether the tooth pulp is alive, dead or inflamed your dentist will perform the following tests-

  • Percussion testing: tapping or pushing firmly on individual teeth to identify which ones feel tender. 
  • Pulp vitality testing: this involves holding hot or cold pieces of cotton wool against individual teeth. Failure to feel the temperature change indicates that the pulp may be dead or has shrunk away inside the tooth. An electric pulp tester is a pen-shaped device that also tests the status of the pulp; a tingling sensation will indicate that the pulp is still alive.
  • Dental X-rays: these show the proximity of fillings to the pulp and the presence of inflammation or bone loss around the apex of the tooth.

If it is confirmed that you have a dead or dying pulp, your dentist will assess your general dental health to see if RCT is a viable option. There would be little benefit in spending hours performing RCT on a loose tooth that was likely to fall out within a year. Other factors that your dentist may discuss with you include:

Resolution of symptoms: the pain related to an infection from a dead pulp may persist for several days after RCT or require several dental appointments before it resolves completely. You may prefer to have the tooth extracted rather than face the possibility of continued discomfort even for a short time.

Choice of final restoration: teeth with RCT are more vulnerable to fracturing than teeth with healthy pulps, especially back teeth. To reduce this risk, they should usually be restored with a crown or a filling that covers the whole biting surface. The different options will vary in terms of cost.

Your availability: some RCTs can be completed in half an hour whilst others may require multiple appointments. Reasons for the differences in treatment duration include:

  1. Variations in root canal shape and location - incisor and canine teeth tend to have a single root canal which is usually straight, easy to locate and fairly easy to treat. Molar teeth on the other hand can have 3 to 6 canals which are smaller, are harder to access at the back of the mouth and can be curved or even 'S'-shaped. Some root canals can also be blocked by layers of dentine which makes treatment more difficult.
  2. The cause of the pulp death/damage - a tooth that has been fractured in a sporting injury may have little or no pulp infection and might undergo RCT in a single appointment. Teeth with a lot of infection in the root canals and bone may require several cleaning appointments before the infection has resolved sufficiently to complete the RCT.

Further reading and references

Had it for a while and every so often it gets very sore and swollen, but woke up today and it was bleeding. Anybody have an idea of what it is and do I need to see the doctors about it?

Health Tools

Feeling unwell?

Assess your symptoms online with our free symptom checker.

Start symptom checker