Survival of Replanted Permanent Teeth after Traumatic Avulsion

Introduction: Tooth replantation is the treatment of choice for avulsion, even though its long-term prognosis shows great variability and few studies have adopted survival analysis to evaluate the fate of such teeth. The present study aimed to evaluate both the survival rate of replanted permanent teeth after traumatic avulsion as well as its clinical and demographic determinants. Methods: Records from 576 patients treated at the Dental Trauma Clinic at the Federal University of Minas Gerais, Brazil, were analyzed to collect clinical and radiographic data. Kaplan-Meier curves and a multivariate Cox regression model were used to estimate the probability of replanted teeth remaining functional in the mouth and to determine prognostic factors. Results: The post-replantation survival rate was 50% after 5.5 years. Immature teeth presented an increase of 51.3% in the loss rate (P = .002). Each additional year in the patient's age at the time of trauma, up to the limit of 16 years, reduced the loss rate of replanted teeth by 15% (P < .001). The storage of the avulsed teeth in milk decreased the loss rate of replanted teeth by 56.4% (P = .015) when compared with those kept dry. Conclusions: The overall survival rate after replantation of permanent teeeth was 50% after 5.5 years. Advanced stages of root development, together with the increase in the patient's age at the moment of trauma, up to the limit of 16 years, were good prognostic factors for tooth survival. The storage of avulsed teeth in milk was also associated with enhanced tooth survival after replantation.