THE rotten state of children's dental health has been revealed in a study of 6,200 five-year-olds, in which 50 per cent had already experienced decay.

The census of all state-run County Durham and Darlington schools disclosed figures among the country's worst, showing tooth decay worsening in contrast to national improvements.

While Derwentside Primary Care Group (PCG) was the only area with less than 40 per cent of youngsters having suffered decay, with 37 per cent, the Dales PCG area topped the chart at 60 per cent.

In 18 Dales schools, more than two out of every three pupils had suffered decay - nearly half of the 43 schools found to have such problems.

Sedgefield and Darlington had the next highest levels of youngsters experiencing decay, at 56 per cent each, with Easington on 52 and Durham City and Chester-le-Street on 42.

County Durham and Darlington Health Authority's dental public health consultant David Landes said: "It would be true to say that they have some of the poorest oral health in the country."

He said a scheme to encourage children to drink fluoridated milk in schools could help, as a lack of fluoride was one of the main causes of the problem.

The authority's survey found 47 per cent of the children had active decay at the time of the 1999/2000 examinations.

Mr Landes said: "It's a small proportion of the population that is hit very hard by dental disease."

One reason for the geographical variance, he said, was differing fluoride levels in water, with areas like Derwentside having a high quantity.

Lincolnshire firm Cool Milk For Kids provides a service to 175 schools across the county and 146 nurseries, where children pay 11p a day for one-third of a pint of milk.

Mr Landes said the cost of fluoridated milk was no more than that of ordinary milk and the general health advantages of children drinking milk could last throughout their lives