Only half of all adult New Zealanders have been to a dentist in the past year, a poll has found.
The UMR Research poll also found that 9 per cent of all adults, and 19 per cent of those earning below $15,000 a year, have not been to the dentist for more than 10 years.
The socio-economic skew - only 4 per cent of those earning over $70,000 have not been to the dentist in the past decade - suggests that costs are a leading factor keeping people away from the dentist's chair.
But Dental Association chief executive Dr David Crum warned that those who stayed away would face higher costs later.
"The chances of changing something from being inexpensive to expensive multiply as you leave it longer," he said.
"We have asked the Government particularly for targeted assistance to low-income adults, and we need to really do something about the elderly population because we are all ageing and keeping our teeth, so in the next 20 years we will see a huge change in the number of elderly people who have their teeth and are on fixed or low incomes."
UMR research director Gavin White said he asked 1000 people from UMR's regular online panel about dentistry after seeing a Gallup poll of 178,000 Americans finding that 65 per cent visited a dentist in the past year. His New Zealand survey found only 52 per cent visited the doctor here.
Kerry Dunphy, a Canadian who is marketing manager for New Zealand's biggest dentists' chain Lumino, said Americans went to the dentist because it was covered by health insurance that was often part of their employment packages.
"Forty per cent of dentistry in the US is funded by the patient, the rest is insurance-funded or publicly funded," she said. In contrast, 98 per cent of Lumino's income comes directly out of patients' pockets.
The UMR findings are similar to a 2009 Health Ministry survey of 4900 New Zealanders which found that 47 per cent of adults went to a dentist in the past year.
That survey found the same socio-economic pattern, with dentists' visits in the past year ranging from 34 per cent in the poorest fifth of areas up to 63 per cent in the richest areas.
Visits plunged from 90 per cent at primary school ages (5-11) and 80 per cent at secondary age (12-17), where treatment is free, to just 37 per cent in the youngest unsubsidised age group, 18-24. Visits then climbed slowly to peak at 56 per cent in the 45-64 age group, but dropped again to 48 per cent for those aged 65-74 and 40 per cent aged 75-plus.
About 44 per cent of all adults said they avoided dental care in the past year because of cost.
KidsCan chief executive Julie Chapman, whose charity has teamed up with Lumino to offer free dental care tomorrow to 500 parents of children who receive KidsCan food aid, said paying for dental care was simply not a priority for families that struggled to afford food.
"It would be really great for people who have serious dental health conditions to be able to access free dental care through the health system," she said.
Associate Health Minister Tariana Turia, who is in charge of oral health, said: "It is an anomaly that what is clearly a primary health issue is so expensive and the Government should do more to subsidise oral health care for adults on low incomes."
Public hospitals now offer "emergency relief of pain" for a minimal fee, which in Auckland is $40, but this is limited to one tooth extraction.
Work and Income pays beneficiaries for dental treatment costing up to $300 a year and lends them up to a further $200.