title: A comparative evaluation of efficacy of protaper universal rotary retreatment system for gutta-percha removal with or without a solvent.
abstract: OBJECTIVE
  The aim was to evaluate and compare the efficacy of ProTaper Universal rotary retreatment system with or without solvent and stainless steel hand files for endodontic filling removal from root canals and also to compare retreatment time for each system.
  
  
  METHODS
  Thirty extracted mandibular premolars with single straight canals were endodontically treated. Teeth were divided into three major groups, having 10 specimens each. Removal of obturating material in group 1 by stainless steel hand files with RC Solve, group 2 by ProTaper Universal retreatment instruments and group 3 by ProTaper Universal retreatment instruments along with RC solve was done. Retreatment was considered complete for all groups when no filling material was observed on the instruments. The retreatment time was recorded for each tooth. All specimens were grooved longitudinally in a buccolingual direction. The split halves were examined under a stereomicroscope and images were captured and analyzed. The remaining filling debris area ratios were considered for statistical analysis.
  
  
  RESULTS
  With ANOVA test, statistical analysis showed that there was statistically no significant difference regarding the amount of filling remnants between the groups (P < 0.05). Differences between the means of groups are statistically significant regarding the retreatment time.
  
  
  CONCLUSIONS
  Irrespective of the technique used, all the specimens had some remnants on the root canal wall. ProTaper Universal retreatment system files alone proved to be faster than the other experimental groups.
authors.affiliation: Department of Conservative Dentistry and Endodonties, Vishnu Dental College and Hospital, Vishnupur, Bhimavaram, West Godavari District, Andhra Pradesh, India.
authors.forename: M Sita Ram
authors.initials: MS
authors.lastname: Kumar
authors.forename: Girija S
authors.initials: GS
authors.lastname: Sajjan
authors.forename: Kalyan
authors.initials: K
authors.lastname: Satish
authors.forename: K Madhu
authors.initials: KM
authors.lastname: Varma