The Dental Association says it is time the Government stepped in to the fluoride debate and took the responsibility off local government.
The Hamilton City Council has voted to restart its fluoridation programme after councillors voted in July last year to stop treating the water supply.
Association board member John Boyens says the issue is a health one and should not be left to local authorities to decide.
Mr Boyens says it's time that Health Minister Tony Ryall intervened and made a national binding policy to fluoridate all water supplied in New Zealand.
But the ministry is sticking by its policy of letting local authorities decide.
In a statement on Friday, it says it provides extensive public information about fluoride and that allows the public through local authorities to make up their own mind.