Partial replacement of the dentin-pulp complex by periodontal supporting tissues in a traumatically intruded primary maxillary incisor.

This paper describes a case of a 9-year-old patient who presented a completely intruded primary maxillary incisor because of a traumatic injury sustained at the age of 3 years. After tooth extraction, histological analysis revealed that the dentin-pulp complex was partially replaced by cementum, periodontal ligament and alveolar bone. No signs of ankylosis were noticed. It is suggested that the lack of spontaneous re-eruption of the traumatized primary tooth after 6 years could be due to the development of functional periodontal supporting tissues in the pulp chamber secondary to the traumatism.