The primary molar teeth should be kept in the mouth until age 10-12 years. These teeth help children chew food, but importantly they hold space for the permanent teeth that will eventually come up in their place.  If a primary molar is lost early, the teeth in front and behind will move into the gap, meaning that when the permanent tooth tries to push through there is no room. 

This creates a dental crowding problem, which may need to be corrected by orthodontics. If a tooth is beyond saving it may need to be extracted.  In certain situations we will recommend immediate placement of a space maintainer (‘spacer’) to prevent movement of the teeth on either side into the space. These are not always necessary and should not be fitted unless the tooth brushing is excellent, as otherwise the teeth under the spacer may go bad.