The survey, carried out by the British Dental Health Foundation and Oral B for National Smile Month, found that 20 per cent of under-five year olds are being left to brush their teeth unsupervised.

25 per cent of parents believe that children do not need to brush twice a day the study reported, while 23 per cent do not think it important for children to avoid fizzy drinks and 67 thought brushing for one minute is recommended rather than the suggested two minutes.

Commenting on the survey findings Chief Executive of the British Dental Health Foundation, Dr. Nigel Carter said:

"These results really are very worrying and help explain why around half of children under the age of five currently have tooth decay here in the UK.

"Teaching children good dental habits is vital. Not only has research shown that people who learn good habits as children are far more likely to carry them into adulthood, but taking bad habits into adulthood will cause gum disease and this has been linked to all manner of serious conditions including diabetes, strokes, heart disease and low birth weight babies.

"Oral health is often seen as of secondary importance to general health but that is wrong. The 'Brush for Health' theme of this year's National Smile Month will make the public aware of the very real links between oral health and overall body health."

Dr Gary Stephenson, Oral-B dental expert added: "Developing a good tooth brushing habit in the young is critical to caring for your child.  Choosing the right toothbrush and paste is important in making tooth brushing an enjoyable activity especially with parental encouragement.  Only you as a parent can ensure your child has a good brushing technique from an early age by being with them and encouraging good practice.  If you are unsure ask your dentist or hygienist.  It can also be one of those special bonding moments with your child, as you encourage them to look after their milk teeth to keep the tooth fairy happy and ensure they develop the habits to look after their second teeth"

The survey also suggested that many UK children carry their bad oral healthcare habits on into adulthood.  It found that while 29 per cent of UK adults suffer with bleeding gums, almost half of those ignore it or brush their teeth more softly to avoid aggravating it.