THE Greens have promised to campaign for more than $8 billion for a national dental health care program for all Australians by 2018.

Under the expanded Denticare policy, released on Tuesday, the current $2.7 billion scheme for children would be expanded to all citizens over five years.

Party health spokesman Senator Richard Di Natale said that from January the existing policy negotiated with the Labor Government would give 3.4 million children access to free dental care up to $1000 a year.

"We are prioritising those people who need coverage the most so pensioners would be the first additional group to be covered, followed by all concession card holders," Senator Di Natale said.

"Leaving dental out of Medicare created an enormous gap in Australia's universal healthcare system."

While the policy was costed by the Parliamentary Budget Office, The Greens policy document did not explain how the funds needed would be raised.