The British Dental Association (BDA) says dental health inequalities across the country could "go from bad to worse" after the coronavirus pandemic if the Government does not support services which have faced disruption.
Public Health England data shows that 8.5% of children surveyed in Northumberland over the last two school years had experienced some form of dental decay although this was based on a small number of children examined – just 65.
The figures also show the oral health of pre-schoolers in the has improved since the survey was first carried out in 2013 found 9.7% of children had tooth decay.
The BDA says that tooth decay is the number one reason for child hospital admissions nationally.
Eddie Crouch, BDA chairman, said: "Sadly, millions of missed appointments, lockdown diets and the suspension of public health programmes mean things are set to go from bad to worse when it comes to health inequality.
"It's time for some real commitment from the Government if we're going to avert an oral health crisis."
A Department of Health and Social Care spokesperson said: “The Government is committed to the effective measures to improve the oral health of children, which is why we will be consulting on supervised toothbrushing and removing barriers around water fluoridation.
“We have also taken significant action to reduce the sugar content in food and drink.£”
They added that a new NHS rule requiring dental practices to hit 60% of their pre-COVID activity until October "is expected to improve access to vital dental services."