Sodium hypochlorite (bleach) has long been routinely used in endodontic treatment because of its antimicrobial and tissue dissolving properties. But the use of any corrosive agent carries risks and we have received a small number of claims after patients suffered chemical burns and tissue necrosis from bleach which escaped into the surrounding tissues during root canal treatment. It can be difficult to defend such claims successfully if appropriate precautions have not been taken and noted in the clinical records.

The British Endodontic Society, the American Dental Association and other international professional organisations offer valuable risk management advice on the use of sodium hypochlorite. And among relevant literature is a particularly helpful 2007 article in the British Dental Journal by Spencer et al. Key points of the article include:

  • Have practice procedures to control exposure to hazardous substances and deal with accidents, in line with the Control of Substances Hazardous to Health Regulations (COSHH). The GDC expects you to be aware of the law and obligations that apply to your clinical practice (GDC Standards for the Dental Team (2013), para 1.5.1).
  • Ensure patients and practitioners are wearing personal protective equipment (PPE), including impermeable bibs and well-fitting safety glasses.
  • Use a sealed rubber dam to isolate the tooth being treated.
  • The irrigation needle should be appropriate for the purpose.
  • Use minimal pressure to reduce the risk of excess fluid being forced into the canal and in turn escaping into the surrounding tissue.
  • If something goes wrong during treatment, tell the patient straight away and explain what you need to do next, e.g. hospital treatment. The GDC expects you to record all patient safety incidents and, if appropriate, report them promptly to the appropriate national body (GDC Standards for the Dental Team (2013), para 1.5.4).
If something goes wrong during treatment, tell the patient straight away and explain what you need to do next

Domestic bleach

A further question sometimes raised by members concerns the dento-legal implications of using domestic bleach rather than medical quality sodium hypochlorite.

We are not aware of any national guidance on this or on the best concentration of sodium hypochlorite to use for irrigation. However, from a practical viewpoint, it's worth considering the potential difficulties of justifying the use of household bleach bought from a supermarket to a non-dentist, such as a judge or a lay member of a GDC fitness-to-practise panel, especially if it has caused harm to the patient.


This article was correct at publication on 29/04/2015. It is intended as general guidance for members only. If you are a member and need specific advice relating to your own circumstances, please contact one of our advisers.

Rupert Hoppenbrouwers

Senior dento-legal adviser

Rupert Hoppenbrouwers (BDS LDSRCS) was head of the DDU until his retirement at the end of 2015. He is a former general dental practitioner and was director of the School of Dental Hygiene at University College Hospital, London, from 1980 to 1986. He has lectured and written widely on risk management and dento-legal matters, has previously chaired the UK Dental Law and Ethics Forum, and has a particular interest in complex ethical and legal issues affecting dental members.

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