Effectiveness of Four Rotary Retreatment Instruments During Root Canal Retreatment

Abstract

The purpose of this in-vitro study was to investigate the residual root canal filling material after retreatment of root canals using stainless steel hand files, and four nickeltitanium retreatment instruments. Materials and Methods: Seventy five extracted mandibular premolars were instrumented and filled. The samples were randomly divided into 5 groups (n=15) and retreated using Hedstrm files, Mtwo R, R-Endo, ProTaper Universal Retreatment, and D-RaCe systems. The roots were digitally radiographed, then grooved split longitudinally to investigate the area of remaining filling material. The time of retreatment and the instruments fracture were also recorded.