Dental erosion involves demineralisation where teeth are attacked by acids and tooth enamel is consequently worn away.

BBC: Tea 'good for teeth'

More than half of those aged between four and 18 also suffered from dental erosion - when acid found for example in fizzy drinks and some fruit juices directly rots the teeth.

BBC: Dentist

But despite the incidence of tooth decay and erosion, the majority of youngsters do seem to be aware of the importance of dental hygiene - two thirds of them brush their teeth twice a day.

BBC: Dentist