title: A comparative evaluation of root canal area increase using three different nickel-titanium rotary systems: An ex vivo cone-beam computed tomographic analysis.
abstract: OBJECTIVE
  The present study was undertaken to compare and evaluate the area increase of root canals with ProTaper, iRaCe and Revo-S systems using cone beam computed tomography for analysis.
  
  
  METHODS
  Forty five extracted human mandibular premolars having single canal and straight root were collected. Teeth were randomly assigned to three groups (n=15). Samples were decoronized by maintaining root length at 14 mm. Pre-instrumentation cone beam computed tomography scan was done after stabilizing the samples on wax blocks. The working length was determined at 1 mm short from the apical foramen by using a ISO 15 K-file tip protruding at apical foramen. Preparation was carried out according to the manufacturer's instructions. Finally, canals were instrumented upto 30/.06 apically for each group. After each instrumentation, root canals were irrigated with 2ml of 3% sodium hypochlorite solution followed by 2 ml of 17% EDTA solution. Final irrigation was done with 5ml of saline. Post instrumentation cone beam computed tomography scans of all samples in the 3 groups were acquired.
  
  
  RESULTS
  Mean percentage of area increase in different thirds of the canal was highest for ProTaper followed by i-RaCe and Revo-s system which was statistically significant.
  
  
  CONCLUSIONS
  Root canal area increase was highest for ProTaper followed by i-Race and Revo-S systems.
authors: Department of Conservative Dentistry and Endodontics, Regional Dental College and Hospital, Guwahati, Assam, India.
authors: Adrija
authors: A
authors: Deka
authors: Department of Conservative Dentistry and Endodontics, Regional Dental College and Hospital, Guwahati, Assam, India.
authors: A C
authors: AC
authors: Bhuyan
authors: Department of Conservative Dentistry and Endodontics, Regional Dental College and Hospital, Guwahati, Assam, India.
authors: Darpana
authors: D
authors: Bhuyan
keywords: Area increase; ProTaper System; Revo-S System; cone beam computed tomography; i-RaCe System