More than 2500 Auckland children have not had a dental check up for four years.
Dentists worry many could be in pain, while others could be on track for a lifetime of problems with their teeth.
The president of the Dental Association, Katie Ayers, says the number is surprising and frustrating.
She told RNZ's health correspondent Rowan Quinn the children would not be getting the checks and preventative measures that could stop them getting the decay.
