Continued apexogenesis of immature permanent incisors following trauma

two cases of trauma to immature teeth are described which differed signific antly in their initial severity. However, both subsequently presented with continued apical root formation. In the two cases a histological examinatio n after tooth removal confirmed continued apical development of the traumat ised immature teeth distant to their respective coronal portions. These cas es highlight the resilience of the root sheath of Hertwig to trauma.