Analysis of the association of clinical factors and IL4 gene polymorphisms with root resorption in avulsed teeth after 1 year of replantation.

No association between root resorption and IL4 gene polymorphisms was observed. An extra-alveolar time of more than 1 h was associated with a susceptibility for external root resorption. Replanting the tooth in its socket immediately is the most important factor to maintain a healthy root surface.