EVALUATION OF ENDODONTIC RETREATMENT ROTARY FILE SYSTEM FOR REMOVAL OF GUTTAPURCHA AND THREE DIFFERENT SEALERS- AN INVITRO STUDY

Objectives: The aim of this study was to compare and evaluate the efcacy of rotary ProTaper retreatment (PTR) les, in the removal of lling materials from the root canal system of extracted human mandibular rst premolars. Materials and methods: Sixty human mandibular rst premolars were collected, stored, and cleaned. Standardization of all specimens was done to 15 mm length. All specimens were prepared upto F2 size using the PTU le system and obturated with F3 gutta-percha using AH 26, Znic oxide and Gutta ow sealer. After coronal sealing, all teeth were stored for 1 week and then divided into three groups of 1. Time taken for retreatment in each group was noted. After retreatment, all teeth were longitudinally sectioned, imaged under stereomicroscope, and scored. Data analysis was done using one-way analysis of variance . Results: ProTaper retreatment les showed signicantly less residual lling material with respective of sealer used. Conclusion: In all groups amount of remaining debrise is proportion on type of sealer used N. In all groups ProTaper retreatment les were most efcient in the coronal third, whereas PTN les were most efcient in the middle and apical third. Clinical signicance: Irrespective of the le system used, root lling material is left behind, which may lead to failure of the treatment, and so an efcient retreatment le system is required.