The purpose of this study was to identify the variables that significantly influenced the survival of incisors replanted after extended extra-alveolar duration at The Hospital for Sick Children, Toronto, Canada, between June 1988 and December 1993. Survival analysis was used to identify variables that significantly influence the retention of replanted incisor teeth. Survival was defined as the time that elapsed between the replantation of an avulsed incisor and the time it was finally lost. Information on 9 variables was collected for 38 patients (25 males; 13 females) and 52 replanted permanent maxillary incisors. The mean extra-alveolar duration for the sample was 123 min. The mean follow-up interval was 942 days (range: 364-2126 days). Incisors replanted with open apices had a significantly decreased survival compared with teeth with mature apices (P = 0.04; relative risk 4.2). There was also a significant association between increased survival and obturation of the root canal with gutta-percha and sealer (P = 0.006; relative risk 10.0). A trend towards improved survival of replanted incisors was found for children older than 11 years old at the time of replantation (P = 0.09; relative risk 2.8). These results are consistent with previous studies and may assist clinicians and parents in the decision-making process associated with the management of avulsed teeth in children.