Dental infections, also called dental abscesses, are collections of pus and / or bacteria that accumulate within the tooth pulp of a tooth. There are several levels of infection ranging from mild to severe. Infections of the teeth usually involve the nerves in the center of the tooth. When the root dies, the infection has the opportunity to spread to the surrounding tissues, gums, bones and teeth. The symptoms of tooth infections are very similar to those of tooth abscess including.