Aim of the study: To study the effectiveness of using dental operating microscope and ultrasonics with Hedstrom files in removing gutta-percha and sealer from root canals. Materials and Methods: Twenty single straight rooted, extracted human mandibular premolars were prepared, filled with gutta-percha and sealer (Zinc oxide with eugenol). Specimens were then divided into two groups (N1=N2=10), and root filling material was removed using H-files with Eucalyptol (group 1); H-files with Eucalyptol, followed by using microscope with ultrasonic tip (group 2). After retreatment, the efficacy of each technique was examined at 8× magnification with a stereomicroscope then the images were analyzed using Auto-CAD 2010 according to Hulsmann and Stotz scale. Data were statistically analyzed using Mann–Whitney U-tests.