The study aims to compare two methods of repairing and saving a badly damaged or infected tooth. One method is called root canal treatment (RoCT) and the other (new method) is called pulpotomy. RoCT involves removing the damaged area of the tooth including the tooth nerve (called the pulp), cleaning, disinfecting and sealing it. Pulpotomy however attempts to preserve as much of the tooth nerve as possible (keeping the tooth alive). RoCT is more expensive and painful. Therefore, some patients delay or avoid getting treated, resulting in later complications treated in an emergency setting. This research will aim to show that pulpotomy is less painful, less involved (i.e. less invasive), less time consuming and consequently more cost effective. Long term costs of dental treatment as well as the improved quality of life will therefore offer benefits for patients, public and the NHS who use dental services. Caries (tooth decay) is the most common diseases in the world. The NHS spends at least £3.4 billion per year on dental visits or at dental hospitals. This does not include private (societal) costs to individuals who do not qualify for NHS dental treatment. Consequently, those who end up avoiding or delaying treatment result in complications often treated through the NHS. We have therefore chosen a randomized controlled trial design, a gold standard method to compare the effectiveness of the two treatment options. The participants will be 168 dental patients (male or female) from different parts (London and Liverpool) of the UK so that results can be generalized. This design was considered in consultation with a member of the public (a co-applicant) who will be involved in the trial from the start to completion. The results will be published and discussed at conferences as well as through our patient and public network.

Inclusion Criteria:

• • Dental patients from an acute (secondary care) setting from at least three UK centres (including King's College London Dental Institute, Denmark Hill and Liverpool).

  • Male or female (aged >16) able to provide informed consent in otherwise good general health with at least one molar tooth with clinical symptoms of irreversible pulpitis caused by caries, requiring RoCT (endodontic treatment).
  • Patients enrolled will have clinical symptoms of irreversible pulpitis who need treatment.

Exclusion Criteria: Exclusion Criteria:

• The presence of fistulas or swelling
• Anterior teeth or premolars
• External or internal root resorption
• Multiple teeth with carious lesions in the same quadrant,
• Pregnant women, in view of requirements for radiographs.
• Patients younger than 16.
• Patients unable to give consent.
• Patients who have been administered antibiotics in the previous month.
• Immunocompromised patients
• Teeth with hopeless prognosis with caries extended into root dentine and with tooth margin at crestal bone level