Can teaching a dog to bark backfire?

Mine shows teeth sometimes and sometimes opens and closes her mouth before anything comes out. I don't think it will backfire it depends how they act before and after mine is perfectly fine after the speak even though she will bare her teeth, i think its just part of her way of barking, if you train him to only bark when you say speak and don't encourage it when you haven't asked for it it should be fine. But if you are really concerned I would stop.