Apical transportation associated with ProTaper® Universal F1, F2 and F3 instruments in curved canals prepared by undergraduate students - Brito-Júnior, Manoel; Faria e Silva, André Luís; Camilo, Carla Cristina; Pereira, Rodrigo Dantas; Braga, Neilor Mateus A.; Sousa Neto, Manoel Damião de (Journal of Applied Oral Science, 2014)