Dentists have a legal duty to obtain valid consent from a patient. Additionally, GDC Standard 3 states that valid consent must be obtained from a patient. Consent must be gained prior to any investigation or treatment being carried out. 

The basic principles for consent are that:

• It must be voluntary – the individual should make the decision themselves and free from pressure (whether that is by a clinical staff member or a friend/family)
• It must be informed – the person must have all the required information about the nature, reason, benefits, material risks and alternatives of any proposed treatment/investigation. They should also be aware of the likely outcome should they not have the treatment/investigation carried out
• The person must have capacity – they must be able to understand the information and weigh it up to make an informed decision

Consent may be implied (for example, if a patient sits in the dental chair and opens their mouth for an examination) or express (where written or oral consent must be obtained from the patient).