Loose tooth
A tooth that has begun to move in its socket — a fixed part of the body announcing that it may not stay.
A loose tooth in a dream is the dream's image of a fixed part of the body announcing that it may not stay. Teeth are supposed to be solid; a loose one is information that something structural has gone wrong. The dream brings the loose tooth when something in your life — a competence, a piece of your reliability, a feature you took for granted — has started to show movement where it used to be set. A loose tooth carefully nursed, with the socket supported, is the dream telling you the damage is being addressed. A loose tooth that falls out altogether is the dream noting that the fixed feature has been lost, and the smile, the speech, the bite that depended on it have to reorganise.