Many histological studies, animal experiments and also human studies during the past 30 years have proven that the use of general anaesthesia in young children under the age of four can have a permanent effect on the brain, which is still developing, and can therefore cause learning and/or behaviour problems later in life. This knowledge has to be taken seriously into account in the discussion with parents whether general anaesthesia is really necessary for the treatment of Early Childhood Caries in very young children.