I got a new crown about a month ago. When I massage my gums, I smell and taste something bad emanating from the crown area. It's not a very strong taste or smell but it really bothers and worries me. I do not remember but I think the tooth had a cavity that was filled before the crown was placed upon it. I told my dentist about the smell and he says that I am one of those patients that has bacteria and that's just the way it is. He says it happens through the nose where the air runs to my mouth and feeds the bacteria that causes the bad smell. I don't have any nose problem, sinusitis or sinus infection so I don't know what he is talking about!!!! I didn't have bad breath before. He also says the smell has nothing to do with the crown and that I have to floss and use mouthwash. I brush my teeth after each meal, floss often and no matter how much mouthwash I use, I still taste and smell something wrong. I just don't want to hear in the near future that I have gum disease because my dentist didn't take care of the problem. What can cause the bad taste from the crown?