When a baby molar is taken out prematurely, placement of a space maintainer may be required to prevent serious crowding of permanent teeth.
Here is a photograph of a lingual arch space maintainer on a plaster cast. It is fastened to the two permanent molars, locking them in place.
The lower left first baby molar is missing on this patient. Left alone, the left first molar (on our right side as we look at the cast) would drift forward, pushing the second baby molar and causing it to block the eruption of the permanent tooth that is supposed to come up in this space.
Since they are preventive in nature, many dental insurance plans offer 100% coverage on space maintainers.
Space maintainers should be checked regularly to make sure they don’t come loose. If they do, the patient should see the dentist right away to re-cement it. Once the permanent tooth erupts, the space maintainer is no longer needed and is removed.