Comparing the effectiveness of Gutta-Percha and Resilon removal using two different techniques in endodontic retreatment

Abstract

Background: The goal of nonsurgical retreatment is the removal of all filling materials to completely disinfect the whole root canal space. Recently Resilon obturating system has been introduced as a root canal filling material. Objective: To compare Gutta-percha and Resilon removal, using ProTaper rotary files with chloroform or heat in endodontic retreatment. Methods: This experimental study was performed on sixty-four human single-canal lower jaw extracted premolars at Dental School, Qazvin University of Medical Sciences during 2010. Following separating teeth crowns from the cementoenamel junction, canals were instrumented using step-back technique with k-files. Later, the extracted teeth were randomly divided into four groups of 16 teeth. Canals were obturated with either gutta-percha/AH26 (groups 1,2) or Resilon/Epiphany (groups 3,4). Retreatment for groups 1 and 3 was performed with ProTaper system and heat and for groups 2 and 4 with ProTaper system and chloroform using crown-down technique. Once the retreatment procedure was completed and justified, roots were sectioned longitudinally and examined under stereomicroscope. Data were analyzed using T-test, Kruskal-Wallis, and Mann-Whitney tests. Findings: In all groups, some filling materials (core material and sealer) were seen on the canal walls. Although, amount of Gutta-Percha/AH26 and Resilon/Epiphany system residue were similar, the amount of residual materials in group 4 was significantly more than other groups (P