Hi, I hope someone can answer this. I have been having a sour taste in my mouth on and off for a few weeks. I notice, maybe from clenching, that the mucous membrane on the inside of my cheek is not smooth. It seems like the taste is coming from there. The dentist couldn't see any disease and doesn't have an answer. Yesterday my mouth tasted salty, really horrible, I couldn't eat anything without it tasting disgusting. Today it's back to sour. Chewing Orbit makes it worse because when the gum loses its taste, it turns sour and then I feel worse. Any idea what can cause this? Can an abrasion on the cheek make my mouth taste nasty?