This paper analyzed the distribution of treatments for permanent teeth with necrotic pulps and open apices according to the stage of root development. Dental records from all root canal procedures performed in permanent teeth with necrotic pulps and open apices over a period of 14 years by residents of the Speciality of Endodontics, University of Guadalajara, Mexico, were analized. Records from 206 treatments were mainly divided into the following 3 different stages according to criteria described by Cvek: stage IV (n = 79, 38.3%), stage V (n = 66, 32%) and stage III (n = 53, 25.7%). Few cases involved the initial stages of root development (stages I and II) (n = 8, 3.8%). Such teeth were submitted to four different treatments: MTA apical barrier (n = 69), Ca(OH)2 replacements (n = 34), gutta-percha (n = 67) and a plug of Ca(OH)2/gutta-percha (n = 36). The teeth with intermediate root development (Cvek stage III) showed a predilection for the MTA apical barrier and Ca(OH)2 replacement techniques (P ? 0.001). Furthermore, the stage of root development did not influence the apical extent of the root filling. The finding of permanent teeth with necrotic pulp and open apices is not exclusive to young patients with an open apex. Moreover, teeth with fragile, irregular and divergent apical morphologies, such as Cvek?s stages´ I and II, were not common and may be considered to be unusual findings. The diverse endodontic procedures were reliable regardless of the stage of root development.