Timing of extraction of ankylosed teeth to maximize ridge development.

Retaining an ankylosed replanted tooth during jaw growth leads to arrested development of the associated alveolar ridge. As the adjacent teeth erupt and the adjacent alveolar ridge develops, the ankylosed tooth is left in infraocclusion. The severity of the resulting ridge defect depends on the amount of facial growth after ankylosis. The extent of the defect correlates with the length of time an ankylosed tooth is retained during adolescent rapid growth. This case report illustrates the development of an extensive alveolar ridge defect when a replanted tooth became ankylosed and was allowed to remain through an adolescent growth spurt. The change in tooth position is dramatic and reflects the marked difference in ridge development. Clinical guidelines are presented to determine the optimal timing of extraction of ankylosed teeth to maximize alveolar ridge development.