Quebec's dentists are threatening to pull out of the public health system and deprive more than 620,000 people of subsidized care if the premier doesn't intervene in tense contract negotiations.

Dentist association president Serge Langlois said today the provincial health minister can't be trusted during contract talks and Premier Philippe Couillard must intervene.

Langlois says if Couillard doesn't get involved the majority of his 4,300 members will leave the public system by the end of August.

He says Health Minister Gaetan Barrette wants to make changes that will represent a 12 per cent decrease in the annual income of generalist dentists across the province.

Langlois says his association represents more than 95 per cent of all generalist dentists in Quebec and a strong majority will choose to leave the public system if Couillard doesn't intervene.

The collective agreement between the government and generalists expired in 2015.