Parents' bad habits and sweet fruit juices among causes of the problem

Schools must teach children to brush their teeth during breaks from lessons to halt shocking levels of decay, the health watchdog has said.

It blames parents’ bad habits and sugar-laden diets including fruit juice for rotting the teeth of thousands of youngsters.

Senior dentists say the problem is so severe that children as young as three are having all 20 milk teeth extracted because they have all decayed.

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Teachers' unions say that it is parents' responsibility to ensure that their children brush their teeth correctly

Now, in guidance issued today, the watchdog NICE is instructing staff at primary schools and nurseries to hold supervised brushing sessions at least once a day.

But teaching unions said it was parents’ responsibility to ensure children brushed their teeth and there are concerns it will cut into learning time.

Nonetheless, the guidelines urge staff to issue children with two sets of toothbrushes and toothpaste – one to keep at school and another to take home in case they don’t have one.

The watchdog says some parents have never taught their youngsters how to brush their teeth and it is rarely done.

Teachers will be urged to ask about brushing habits at parents’ evenings and offer advice on how to register with a dentist for check-ups.

Latest NHS figures show 25,800 children aged five to nine are admitted to hospital with tooth decay every year – and the number has risen by 14 per cent in three years.

Many will have been in severe pain for weeks and will need to have rotten teeth removed under a general aesthetic.

Government group says the problems of tooth decay have improved but worse among poorer households

Professor Mike Kelly, director of the Centre for Public Health at NICE, said: ‘Many children … eat too much sugar and don’t clean their teeth with fluoride toothpaste.

‘As a society we should help parents and carers give their children the best start in life and act now to stop the rot before it starts.’

Professor Elizabeth Kay from the Peninsula Dental School in Plymouth, who helped draw up the guidelines, said: ‘Little children are being anaesthetised and we are just taking out parts of their body.

‘It’s horrific, it’s like a battlefield. I have personally seen a three-year-old have a “clearance”, which is where every tooth is taken out. It’s not that uncommon for children to have eight teeth taken out.’

Little children are being anaesthetised and we are just taking out parts of their body.

NICE says that although levels of tooth decay tend to be far worse among poorer households, it is a problem that affects families across the board.

And while levels of tooth decay steadily improved over the past 40 years due to fluoride in our drinking water, they have recently hit a plateau. Experts think this might be the effects of our increasingly sugary diets.

Some parents assume that it doesn’t matter if children’s milk teeth go rotten as they fall out anyway from about the age of six. But dentists say it has a long-term effect on their gums and results in their adult teeth being wonky or more prone to decay.

Researchers also think tooth decay increases the risk of heart disease as it can result in bacteria entering the blood stream and causing clots.

The guidelines recommend that schools hold teeth brushing sessions once a day for children up to the age of 11. They do not specify when they should take place.

For many children it will be the only time in the day when they brush their teeth.