Methodology: Forty extracted single rooted maxillary central incisors were collected and obturated after cleaning and shaping. Samples were divided into four groups depending upon retreatment method.

Group I: H-FILES

Group II: PROTAPER RETREATMENT

Group III: R ENDO SYSTEM

Group IV: GPX SYSTEM

After retreatment, samples were split longitudinally and observed by scanning electron microscopy. Amount of remaining filling material, smear layer and surface profile within each third of the canal was assessed. Results were subjected to statistical analysis using Mann-Whitney and Wilcoxon test.

Results: In coronal and middle third, the remaining debris and smear layer were effectively removed by Protaper retreatment files and R Endo followed by GPX and Hand files. All techniques left filling debris especially in apical third. All groups showed similar effect in surface profile after retreatment.

Key words: Endodontic retreatment, Rotary retreatment files, Scanning electron microscopy