A serious "childhood oral health epidemic" has been discovered in one in five Canterbury children, and researchers are calling for "system changes and interventions" to help curb the disturbing trend.

Pacific children were found to be most disadvantaged; more than 64 per cent of 5-year-olds have at least one tooth affected by decay in 2018 despite making up a small amount of total participants.

Just 499 Pacific children were involved in the retrospective study out of a total 10,766.

The discovery is in research carried out by a trio of New Zealand academics published in the latest NZ Medical Journal out today.


The researchers, Philip Schluter, Jesse Kokaua and Martin Lee, did an analysis of oral health data of all children aged 5 who attended child oral health services in the Canterbury District Health Board region between January 1, 2018 and December 31, 2019.

Shockingly, decay was discovered in one in five preschoolers and the researchers, from Canterbury and Otago universities, say good oral health "is a basic human right for all children" and are calling for change as it was likely to continue to affect the future of not only children, but society in general.

"Now is the time to act."

Two in every five Pacific children was found to have decay, and more than one in every four Māori children had experienced severe early childhood caries (SECC).

Compared to non-Māori or non-Pacific children, Pacific and Māori children were 2.6 and 2.2 times, respectively, as likely to have had at least one tooth extracted because of tooth decay.

Nationally, in 2018, 64.3 per cent of Pacific children had at least one tooth affected, compared to 59.2 per cent of Māori children and 30.9 per cent of non-Māori/non-Pacific

The pattern was one that was developing on an international scale; Pacific children aged 5 to 9 in the United States also had much poorer oral health than their national

It was a disappointing discovery for researchers who found that there had been "significant" caries-free rate improvements in recent years; but children of ethnic background had not benefitted.


"While fewer children may be experiencing caries, those who do have caries appear to be more severely afflicted."

The researchers also wanted to debunk the myths that "baby teeth do not matter as they fall out anyway" and "all children eventually get holes in their teeth".

"But baby teeth do matter; the evidence is unequivocal. Early childhood caries (ECC) has significant short- and long-term impacts—both for the affected individual and our society."

Their report states children with ECC could be impacted in multiple ways including experiencing pain, swelling, reduced quality of life, eating limitations, speech articulation, language development difficulties which could ultimately lead to increased absences from school or pre-school and reduced socialisation and self esteem.

As well as that social burden, there was also the cost to the rest of the country which were "substantial and growing".

For the 2017/2018 financial year, district health board funding for oral health totalled $197.2 million, with child oral health services (COHS) accounting for $98.42m, adolescent dental services costing $42.17m, and hospital dental services spending $49.68m.


The cost of dental treatment under general anaesthesia was estimated at $2400 per case, but it could be considerably more, they wrote.

Between 2004/2005 and 2014, the number of children receiving dental treatment under general anaesthetic increased by 66.9 per cent, and hospital admission rates for these treatments was greatest among children aged 3 to 4 years.

The increase in decay was caused by the frequent intake of food and drink containing fermentable carbohydrate - fizzy drinks.

They found that tooth decay did not occur when there was normal commensal plaque; "an ecological change is required to create a pathogenic plaque that leads to more enamel demineralisation than remineralisation".

Tooth decay was the most common chronic disease of childhood and among the primary reasons for hospital admissions of children in New Zealand.

Jonathan Broadbent, of the University of Otago's Faculty of Dentistry, also writes in the journal that the findings suggested the current dental care system wasn't working and it was now time for politicians to take notice.


"[It's] not surprising, since change is needed in order to effect change.

"Only politicians can practice dentistry on the grand scale and effect radical change in
order to get different results. What will be the next big thing in prevention to improve
oral health of New Zealand children?" he asked.

Dentistry was a neglected area of health policy.

"'Wicked problems' are those which have deep social roots that can't be solved
from inside the healthcare system — oral health inequalities have been described as
such. Here we have a wicked problem that is a neglected one too."

Troubling teeth

• 10,766 children surveyed
• 8445 [78.4%] non-Māori/non-Pacific
• 1822 [16.9%] were Māori
• 499 [4.6%] were Pacific
• Overall, 1980 [18.4%] had severe tooth decay