COMPARATIVE EVALUATION OF SINGLE VERSUS MULTIPLE CONTINUOUS ROTATING FILE SYSTEMS USED IN THE RETREATMENT OF TEETH OBTURATED BY COLD LATERAL COMPACTION AND WARM VERTICAL COMPACTION : AN IN VITRO CONE BEAM COMPUTED TOMOGRAPHY STUDY ENDODONTIC RETREATMENT OF DIFFERENT TECHNIQUES OF OBTURATION BY TWO DIFFERENT FILE SYSTEMS

Abstract

Introduction : An ideal instrument for endodontic retreatment has to allow complete removal of gutta-percha in a short duration, without debris extrusion or alteration of the root canal space as well as no instrument separation or occurrence of other unwanted events, regardless the obturation technique used. Multiple retreatment file system offers specific design to remove obturation material from root canals. The latest innovations in endodontic instrumentation with design and metal treatment led to the development and application of new single-file systems.

Aim: The aim of this in vitro study was to compare and evaluate single versus multiple continuous rotating file systems used in the retreatment of teeth obturated by cold lateral compaction and warm vertical compaction.

Methods and Materials: The root canals of 68 extracted human mandibular single-rooted premolars were prepared and randomly divided into two groups. The root canals were obturated using cold lateral condensation in group I and warm vertical compaction in group II. respectively. Then specimens in each group were randomly divided into two subgroups for retreatment with Hyflex Remover and Protaper Universal Retreatment file system. Pre and post retreatment, cone beam computed tomography evaluation was done to check the volumetric analysis. Also, time analysis was done to measure the time taken by the instrumentation while removing the obturating material. A p-value≤0.05 was considered as statistically significant. The data was analysed using the one-way ANOVA followed by Tukey’s post hoc test was applied.

Results: The remaining filling material in the canals treated with Hyflex R in WVC was highest being 12.1%. Time taken by Hyflex R in WVC was the highest 140.2sec. Conclusion: ProTaper R removed filling material more efficiently compared to Hyflex Remover and took less time to remove root filling material in both of the obturating techniques.