Apical extrusion of root canal filling material during the removal of gutta-percha and resilon

Abstract

Introduction. Root canal filling material may be extruded during retreatment through the apical foramen and cause flare-up or chronic infection. The aim of this study was to compare the apical extrusion of gutta-percha and resilon filling materials during retreatment using hand and rotary instruments. Methods. Sixty extracted single-rooted teeth with single, straight canal were selected. Canals were prepared with ProTaper Universal rotary system to a size F2. Two groups (30 teeth in each) were filled with gutta-percha or resilon points, respectively. In both groups teeth were randomly divided into the three subgroups (10 teeth in each), based on the instruments used for retreatment: Hedstrom hand files and two rotary groups- ProTaper and Twisted File instruments. Apical extrusion was detected visually, using a 4-degree scoring system. Mean scores were calculated and analyzed statistically (t-test and ANOVA). The level of significance was set at p < 0.05. Results. Under tested experimental conditions, the type of canal filling material did not have significant effect on the results of apical extrusion during retreatment. Significantly more material was extruded in the resilon group when manual, Hedstrom file was used (1.80 ? 1.13) than rotary ProTaper (0.60 ? 0.70) and Twisted File (0.50 ? 0.71). Conclusions. The use of a rotary technique is recomended to minimize apical extrusion, especially when resilon obturation material is removed during retreatment.