In the past NHS orthodontic treatment has been given to Lincolnshire residents living near the Cambridgeshire border due to their proximity to the city, but NHS Peterborough has stopped offering the service to people living outside of the city council boundaries.

And with Spalding's orthodontic services dealing with an 18-month waiting list, patients on the fringe of the county - many of whom are children - may have to travel to Boston to receive care.

Crowland dentist John Hartley said: "It's become a postcode lottery. Traditionally people from this area have gone to orthodontists in Peterborough - they have no alternative unless they pay for private care.

"I think more than 20 per cent of the children treated by NHS Peterborough orthodontists are from outside the area, but now they're being bounced back.

"Historical pathway access is supposed to be honoured by the NHS but it's clear that Peterborough doesn't want to pay for Lincolnshire patients anymore."

NHS Peterborough said that existing appointments for Lincolnshire residents would be honoured, but it will not accept any new referrals.
A spokesman said: "Any new funding that may be spent on orthodontic treatments services to improve waiting times in Peterborough would be spent on Peterborough residents."

NHS Lincolnshire said: "Orthodontic provision is available in Spalding but because of the demand some of the patients may have to go to Boston."