Different methodologies to verify the success of odontologic materials in apicoplasties with retro obturations have been used in marginal infiltration studies for courant. This research objectified to evaluate props up them of infiltration of Rodamine B 1%, in an experimental group, comparing it depth of penetration of the courante with its area of impregnation, in the same samples in apicoplasties with retro obturations. The results had demonstrated to a shunting line low standard (4,79), for the mensuration through the area, and high (15,05), for mensuration through the depth of penetration of the courante. The Mann-Whitney test shows significant statistical differences between groups (p<0,0001). The use of area impregnation instead of dye penetration represents a better way to measure levels of marginal infiltration considered in this research
