Avoiding excessive amounts of sugar is vital for maintaining long-term oral health care, according to one expert.

Damage to tooth enamel is irreversible, associate professor Bernadette Drummond from Otago University’s School of Dentistry, told the National.

She said: “If you dissolve the surface of your teeth there is nothing you can do – it is gone.”

The specialist warned parents that children and teenagers who consume excessive amounts of high sugar items will have corroded teeth and require cosmetic dentistry to prevent further damage.

Ms Drummond recommended having fruit juice no more than once or twice a day and trying not to give very acidic products to youngsters.

She explained how once the harm has been done the only option left is to place crowns on the teeth, which they will have to wear for the rest of their lives.

Dr Philippa Sawyer, chairwoman of the Australian Dental Association oral health committee, recently commented that individuals were often unaware of what foods they should be keeping away from in order to prevent tooth decay, the Herald Sun reported.