More than 10,000 children in Peterborough did not see their dentist last year, which experts say has contributed to the nationwide problem of childhood tooth decay.
Public Health England recommends regular trips to the dentist to stop children needing tooth extractions.
Yet in Peterborough 18,096 children did not visit the dentist at least once in 2017, putting them at risk of rotten teeth and gum disease.
Figures from NHS Digital show that 63% of youngsters, 30,877 in total, had an annual check up.
The importance of regular trips to the dentist is highlighted by the fact that in England the most common reason for under 18s to attend hospital is for multiple rotten teeth extractions.
This is where decay is so advanced dentists are unable to treat it at their surgeries.
The numbers highlight the crisis with tooth decay, and the British Dental Association has said that the low number of check ups could contribute to this.
NHS statistics show that in the 2012/13 financial year there were 36,883 extractions where at least two teeth had to be removed, but by 2016/17 this had risen to 42,911.
As well as regular dental visits, PHE also says cutting down the amount of sugary drinks children consume and brushing teeth twice a day with fluoride toothpaste can reduce decay.
The BDA has urged the government to learn from the dedicated national programmes in Wales and Scotland that have used school outreach and public information to secure successes against childhood tooth decay.
Chairman Mick Armstrong said: "There is no room for complacency when tooth decay remains the number one reason for child hospital admissions.
"Getting kids brushing and seeing a dentist shouldn't be optional extras. Sadly parents are being left without guidance, while politicians seem content keeping costs down and patients away.
"In Wales and Scotland we're seeing record breaking improvements in decay, backed up by public information and outreach in schools and nurseries. England needs more than token efforts.
"Getting kids in the habit of attending is key to life-long oral health, and under 18s should be seeing their dentist at least every 12 months."
In Peterborough the number of children going to the dentist has gone up slightly. In 2017 1,896 more youngsters had an annual dental check up than the previous year. But the figures show adults are not setting a good example for children.
Last year 44.9% of adults in Peterborough visited the dentist once in the last 24 months.
A Department of Health and Social Care spokesman commented: "We are determined to reduce the number of children having teeth extracted because of tooth decay, that's why we're introducing a sugar tax on soft drinks with the most added sugar, which comes into effect next month.
"Access to dental services continues to increase nationally - in 2017, 6.9 million children were seen by a dentist representing 58.2% of the child population."