A district health board (DHB) head says more communities are likely to wind up with fluoride in their water once district health boards (DHBs) take over responsibility for fluoridation decisions.
Health Minister Jonathan Coleman plans to introduce legislation later this year to switch the responsibility from local councils.
Lakes DHB head and DHB chief executives group chair Ron Dunham welcomed the announcement.
He said DHBs would focus on communities that are not fluoridating their water.
"If there are areas that aren't fluoridated, that individual DHB needs to have a look at their policies.
"Take my district health board for instance; one of my councils has already fluoridated, one hasn't."
Mr Dunham said the DHB would work closely with the council that hadn't fluoridated and look at the evidence and population there.
He said councils, communities and iwi would still have a role to play, and DHBs would not be acting in haste to impose any changes.