Will a dogs scent keep bears away? Or would the dog be in danger?

We live out in the highlands most of the summer, and recently the bear population has increased, my mom thinks having a dog around will keep bears away (because of its scent) and as much as i want a dog i think that the dog would be in a lot of danger. Does anyone know if bears or moose will attack a dog often? Or if they are scared of their scent?