[A retrospective study on pulpal tissue prognosis of avulsed permanent teeth in children].

OBJECTIVE: To analyze the pulpal prognosis of replanted permanent teeth in children and to examine the associated factors. METHODS: The samples consisted of 67 children with 81 avulsed permanent teeth treated in Peking University Hospital of Stomatology from 2000 to 2012. Their clinical data of the replanted teeth were collected, and the follow-up period was no less than 12 months. The pulpal prognosis was classified as pulp necrosis and pulp non-necrosis. RESULTS: The replantation within 30 minutes after avulsion led to the most significant increase in pulpal healing (P<0.05). The dental pulp of 80% (4/5) young permanent teeth replanted within 30 minutes remained vital, while all the teeth replanted after 30 minutes developed pulp necrosis within 60 days after replantation. CONCLUSION: The extra-alveolar period significantly affects the prognosis of pulp in immature permanent teeth after replantation. When the extra-alveolar period is more than 30 minutes, the chance of pulp revascularization after replantation is very low, therefore pulp extirpation should be performed.