Almost 60% of children aged one to four did not see an NHS dentist last year, figures show.
NHS Digital data analysed by the Faculty of Dental Surgery (FDS) at the Royal College of Surgeons shows that 57.7% of young children did not see a dentist in 2018.
Among all those aged 17 and under, 41.4% of children did not see an NHS dentist.
In the five to nine age group the figure was 32.7%, and 27.6% for those aged 10 to 14.
Professor Michael Escudier, dean of the Faculty of Dental Surgery, said the figures were disappointing.
He added: “Children who experience early childhood tooth decay are much more likely to develop subsequent problems, including an increased risk of further decay in both their baby and permanent teeth.
“This is partly because extensive damage to the baby teeth can cause abscesses that harm the permanent teeth developing inside the gums.
“It’s so important that a child’s first interactions with the dentist are for simple check-ups rather than more serious treatment.
“Just getting a child into the habit of opening their mouth for a dentist to look at their teeth is useful practice for the future.
“If children only visit the dentist for the first time once they have a problem, the experience can cause fear and lead to poor dental attendance throughout their lives.
“Therefore, we strongly advise that children have their first check-up before they turn one.”
The faculty says parents should register their child with a dentist once their first teeth appear.
After an initial check-up before a first birthday, children should then see the dentist at least once every 12 months.
Prof Escudier added: “We are calling for supervised tooth-brushing sessions to be introduced in nurseries and primary schools across England, as similar initiatives have already been successful in improving children’s oral health in Scotland and Wales.”
Henrik Overgaard-Nielsen, chairman of General Dental Practice at the British Dental Association, said: “Any government that claims to value prevention should not be letting nearly 5 million children miss out on free check-ups.
“The UK has pioneered policies that are transforming children’s oral health. Sadly while countries from Chile to Israel are seeing the benefits, kids in England have been left with a second class system, without a penny of new investment behind it.
“It’s not inevitable that a child born in Pendle will arrive in primary school with 20 times the levels of decay as one born in Surrey. It is a direct consequence of years of inaction at Westminster.”
An NHS England spokesman said: “NHS dental care is free for anyone under 18, and it’s really important for long-term health that parents bring their children to the dentist as early as possible.
“Overall more than nine in 10 people who need a dentist appointment can get one, and while 90,000 additional children saw their dentist in the past year, NHS England is working with the dental profession to help even more young people under five get a check.”