Waikato District Health Board is urging Hamilton City Council to put fluoride back into its water supply following a ruling in Taranaki.
The High Court has thrown out a challenge from lobby group New Health New Zealand, ruling that the South Taranaki district council has legal power to add fluoride to its water.
The subject of fluoridation has also been the source of public debate in Hamilton.
Hamilton city council spokesperson Elizabeth Hughes says the council will review Friday's court decision and consider it at the next council meeting.
Waikato District Health Board's communications director, Mary Ann Gill, says the people of Hamilton have already spoken with a recent referendum showing 70 percent of Hamilton residents want to see fluoride back in the water supply.
"Our view is the excuses are over, let's put it back in."
New Health New Zealand had argued that the council has no legal power to add fluoride to its water in Patea and Waverley, and that in doing so, it was a breach of the right to refuse medical treatment.
However, Justice Hansen ruled there is implied power under the Local Government Act for councils to add fluoride to drinking water and that no further consent is required from the Minister of Health.
The judge also ruled that whilst he accepted fluoridation has a therapeutic purpose, it does not constitute medical treatment.
New Health chairman Dave Sloane says he thinks the judge has got it wrong and they will be appealing against the decision.