Top NSW health and dental experts are boycotting an "open" forum organised by one of the most vocal anti-fluoride campaigners from the US, saying the anti-fluoride activists have as little scientific proof as the anti-vaccination campaigners.

A website promoting a February 21 forum with Professor Paul Connett, a US anti-fluoride activist, says he will hold an "open" panel in Australia - his first of this kind despite numerous previous visits - with pro-fluoridation advocates.

Fluoridation of drinking water is considered one of the 20th century's greatest achievements in health. Credit:Max Mason-Hubers

Professor Connett argues that fluoridation's role in the decline of tooth decay is in doubt, even saying that where fluoridation of the water had been stopped tooth decay had decreased, something disputed by all public health associations.

His site also says representatives from the Australian Dental Association, Sydney University's Dental Faculty and NSW Health have been invited to the meeting, which will be chaired by Sydney dentist Dr Ron Ehrlich, the founder of Sydney Holistic Dental Centre.