An MP’s meet-and-greet visit to a dental practice in their constituency would usually pass without comment. But when the MP is the secretary of state for health and social care, and the practice is not only closed to new NHS patients but actively promoting a private alternative, people take note.

Matt Hancock’s recent visit to the mydentist practice in Mildenhall, Suffolk, has raised eyebrows all the more for his apparent endorsement of its private treatment scheme. “Dentistry has always been a mixed market with some people paying and others on the NHS,” he told the Bury Free Press. “That system has served Britain well for a long time and any ideas for how to strengthen that offer are very welcome.”

Meanwhile, news was breaking on the other side of England of the desperation of David Woodhouse, 62, from Truro, Cornwall, who claimed he had resorted to extracting one of his own teeth with pliers after a fruitless search of up to 100 miles to find an NHS dentist. “The removal itself was considerably less painful than the long-term pain I was experiencing,” he said.

There is a growing sense that NHS dentistry is at – or may even already have passed – a tipping point. A new report by market analysts LaingBuisson suggests that while the “high street” dental sector as a whole remains robust, with forecast annual growth of 2%-2.5% over the next three years, this is down to expanding private care, particularly cosmetic treatments such as teeth whitening and straightening. The report’s author, Philip Blackburn, says: “At the same time, NHS dentistry is falling behind and policy-makers face a clear challenge to ensure demand for NHS dentistry is being met across the UK.”

On LaingBuisson’s figures, the overall UK dental market is worth £7.1bn a year. For 2017-18, the period covered by the report, NHS market share is put at less than £3.5bn. As patients pay almost £1bn of that in NHS charges, this means that they are paying for nearly two-thirds of all non-hospital dentistry.

The dental surgery Hancock visited is of course far from unusual in being closed to new NHS patients: the British Dental Association (BDA) says fewer than one in 10 practices in Hancock’s West Suffolk constituency accepts adult NHS registrations, with just one in five registering children.

Mydentist, the trading name of Manchester-based Integrated Dental Holdings, Europe’s biggest dental chain, which operates almost 650 practices in the UK, says it provides both private and NHS treatment and that some 350 of its UK practices are taking new NHS patients.

Mildenhall is too small to do so and will remain closed to new registrations for the foreseeable future, but the company says Mildenhall is one of its practices offering a “truly affordable private alternative” fixed-price scheme called access mydentist.

Under this scheme, an adult pays £30 for a check-up compared to £21.60 paid by non-exempt NHS patients (many, but not all, people receiving low-income benefits are exempt from paying to go to the dentist). Examination and a small filling costs £79 under the scheme, compared to £59.10 on the NHS. Charges for more complex work are considerably higher, however: a filling, root canal treatment and a crown can work out at up to £639 with access mydentist, compared to an upper limit of £256.50 on the NHS.

Henrik Overgaard-Nielsen, BDA chair of general practice, says: “Patients value a choice between private and NHS dentistry, but Matt Hancock seems content that many of his own constituents have been left with no options.”

If NHS dentistry has not yet passed its tipping point, Brexit may prove the nudge that sends it over. According to a survey for the General Dental Council, which registers UK dentists and counts on its books some 6,300 who qualified elsewhere in Europe, almost one in three of them is considering leaving the country. Asked why, half cited Brexit outright and more than eight in 10 said it was a “significant factor”.

A BDA survey last year found that 68% of English NHS dental practices trying to recruit dentists had struggled to do so. The number of free NHS treatments given to exempt patients plunged by almost a quarter from 8.8 million in 2013-14 to 6.8 million in 2017-18.

Mick Armstrong, the BDA’s chair, warns that “wholly preventable” tooth decay is going unchecked. “The writing is on the wall,” he says. “NHS dentistry can’t be run without dentists.”