Dentists in despair over the growing number of children with rotting teeth say the only real cure is ending poverty.
While the prevalence of tooth decay was declining in most developed countries, it remained stubbornly high in New Zealand, the report said.
One of the report's authors, dental public health specialist Rob Beaglehole, said the high levels of decay in children was appalling.
It was not uncommon to take as many as 10 teeth out of young children's mouths, he said.
"Some as young as 18 months, still in nappies - this is happening on a day-to-day basis, all around New Zealand."
The number one risk factor for poor oral health was poverty, Dr Beaglehole said.
"Children brought up in poverty have more holes in their teeth than people brought up in wealthier families," he said.
"Tooth decay is a socio-economic disease."
Māori and Pasifika families were at even greater risk.
Decay rates higher for Māori, Pasifika children
The latest figures from the Ministry of Health, about the oral health of five-year-olds, showed that nationally, 40 percent of five-year-olds had some tooth decay.
But for Māori children, that figure was almost 60 percent and for Pasifika it was 66 percent.
Māori public health provider Hāpai Te Hauora chief executive Lance Norman said diets high in sugar were a major problem for Māori families, as well as a lack of awareness about how to access free dental services.
But the biggest problem, he said, was workforce shortages.
"It's like primary health care - we don't have enough doctors or nurses for primary health care, we don't have enough dentists to actually cope with the demand," he said.
"Any time in New Zealand where we don't have enough of a particular skill base, it's the high-needs, vulnerable populations that miss out, and generally speaking, that's Māori and Pacific."
Hygiene messages not getting through to parents
Karen Turanga has been a dental hygienist in Waikato for 30 years.
While she did not treat many children, she did treat their parents.
It was apparent that even basic messages about brushing twice a day and flossing were not getting through, she said.
It was important that parents were good role models for their children and played their part in encouraging better oral health, she said.
"We're throwing lots of stuff at the kids, but the adults have to get on board - and to get on board they have to understand that there is an advantage and that there is an ongoing benefit for them and their children.
"Sometimes I think that gets lost - too much science, too many opposing opinions and it just gets too hard."
Manukau Urban Māori Authority Whānau Ora services manager Veronica Henare said the whānau coming to them for help had complex needs and oral health was not a high priority.
"When you've got a whānau that could be on the brink of homelessness or they're about to be evicted, I can assure you the last thing on their mind is oral health," she said.
"It's about how do they ensure that their whānau are not out on the street? How do they ensure they're in a safe, warm environment?"
Wellington dentist Rachel Bridgeman said the adolescent oral health service she worked for had had to come up with ways of getting to those hard-to-reach communities.
"We're prepared to go and pick students up if they have toothache and our mobile facility is not available to them at the time.
"We'll go and collect them in one of our cars to take them to our practice because we know they can't actually make their own way there."
The service had seen a big reduction in the number of older children needing fillings over the last couple of years, she said.
However, it was crucial that oral health education started at a young age.
Mothers should be getting advice about it during pregnancy, so any bad habits could be dealt with early on before they became problems, she said.
That advice should be tailored to the circumstances of each family.
"You can't brush away a high sugar diet that feeds the disease process, so it's really important that we get a clear message across that it's diet first and foremost, what we're eating and drinking," Ms Bridgeman said.
The Child Poverty Action Group has made a raft of recommendations to improve the oral health of children.
- Increasing awareness of the free dental care for children
- More education about oral health
- Developing a national plan to tackle workforce shortages
- Improving nutrition labelling - including labelling about sugar content
- Easy to understand guidelines about the consumption of sugar and sugar-sweetened beverages
- Tighter regulations about the sale and promotion of sugary drinks
This article was originally published by RNZ.