PM Jacinda Ardern promises to deliver two key solutions to New Zealand's dental health 'epidemic'

Fluoride could soon be added to most of the country's drinking water, with the Prime Minister promising to pass a Bill that's been on hold for nearly four years.

It came alongside another dental promise on Wednesday: giving preschoolers free toothbrushes.

More than 5000 children and teenagers have dental surgery under general anaesthetic yearly for preventable problems. Dental decay is the most common chronic health condition in New Zealand, and much more common for the poor - children in the most deprived neighbourhoods are six times more likely to be missing teeth.

David Wallbridge of Family Teeth Matters says New Zealand is in the middle of a "decay epidemic".

The Bill would give water fluoridation powers to District Health Boards and likely extend water fluoridation from 50 percent of the country to at least 85 percent.

The Prime Minister was told it was “the most cost-effective action the Government can take to improve child and adolescent oral health, particularly for those in poverty”.

Passing the Bill could save more than $600 million over 20 years, and the National Party supports the change.

On Wednesday, the Prime Minister appeared to blame former Deputy Prime Minister Winston Peters - and promised to get it done.

"We didn't have the support for it in the last Government... we've got the numbers now and the Minister is doing work on it," she said.

But the National Party says that's rubbish, as it would've helped pass the Bill.

"[It's] hard to explain why this is taking so long," National's deputy leader Dr Shane Reti says. "Why can't this be delivered - you've got two of the main parties agreeing this is important."

Also in the Prime Minister's briefing was a recommendation to give all preschoolers free toothbrushes and toothpaste. It's been a success overseas, and the Ministry of Health put aside $2.5 million a year for it.

A similar programme in Scotland was successful, returning £7.34 for every £1 spent after 10 years.

On Wednesday came a promise it'll happen.

"That project work is underway now," Ardern said. "As I understand they're going through a procurement process, so I hope to see some progress on that fairly shortly."

But there's nothing when it comes to another key recommendation - Labour's election promise of increasing beneficiaries' dental grants from $300 to $1000.

The Minister for Social Development Carmel Sepuloni says there's no real timeframe on delivery - just "sometime this term".

"This term we will deliver on our manifesto commitment to increase dental health grants, ensuring those on low incomes are supported to cover the actual cost of dental care," Carmel Sepuloni, the Minister for Social Development and Employment, said in a statement.

Other recommendations made include extending oral health care past the current age of 17, which Newshub has revealed could cost as little as $148 million for a targeted package, providing dental care to pregnant woman and low-income families, “strengthening cross-agency efforts”, working with DHBs to reduce regional variations in outcomes, and ultimately reviewing the ageing 2006 strategy Good Oral Health for All, for Life.

The Prime Minister's Office would not say which recommendations the Prime Minister asked officials to look at further. 

The briefing comes after Newshub revealed then-Health Minister David Clark chose not to progress any recommendations in a similar briefing in 2018. 

New Zealanders spend about $1 billion per year on private dental care.