A retrospective study of survival of 196 replanted permanent teeth in children

The extra-alveolar period and storage medium are important for the survival of replanted teeth. The aim of this study was to evaluate factors affecting the survival of replanted teeth in children.

Complete dental records of avulsed teeth including age, gender, extra-alveolar time, storage type and period, stage of root development, crown fracture, gingival laceration, alveolar fracture, antibiotics, and splint type and period were obtained. Kaplan-Meier, Cox regression and chi-square tests were used to analyse the risk factors affecting survival (P < 0.05).

The study included 196 replanted teeth with a mean follow-up period of 4.0 years. Forty-two (21.4%), 45 (23.0%), and 109 teeth (55.6%) showed functional healing, inflammatory resorption and replacement resorption. The root resorption incidence of teeth with extra-alveolar time longer than 30 minutes was higher vs teeth with a time of less than 30 minutes (P = 0.010). Physiologically stored replanted teeth showed lower incidence of root resorption (19/31, 61.3%) than those stored in non-physiologic media (94/114, 82.5%) (P = 0.025). Root resorption incidence of teeth stored non-physiologically within 30 minutes and then transferred to physiologic media (25/33, 75.8%) was similar to that of teeth stored physiologically (P = 0.127). Teeth stored non-physiologically for longer than 30 minutes had a significantly higher root resorption incidence (99/113, 87.6%) than teeth stored non-physiologically within 30 minutes (55/83, 66.3%) (odds ratio = 1.726, P = 0.001). Pulp canal obliteration occurred in five of the 56 immature teeth (8.9%) but two of them were later extracted because of replacement resorption. The survival of mature teeth (111/140, 79.3%) was significantly higher than that of immature teeth (39/56, 69.6%) (P = 0.007).

This study suggested that non-physiologic storage within 30 minutes was critical for the periodontal healing of replanted teeth. Replanted immature teeth had lower survival rates than mature teeth.