TITLE:
Shaping ability of thermomechanically treated files in simulated S-shaped root canals
AUTHORS:
Nessrin A. Taha, Ghada A. Maghaireh, Dyana El Sadek, Rafat Bagheri, Mohammad Al-Omari
KEYWORDS:
Keywords: S-Shaped Canal; Twisted Files; K3; Canal Aberration
JOURNAL NAME:
Open Journal of Stomatology,
Vol.3 No.7,
October
30,
2013
ABSTRACT: Aim: the aim of this study was to investigate the
shaping ability of thermomechanically treated files manufactured by twisting(Twisted files)and compare it to conventional rotary
system (K3, Sybron Endo, Orange, CA) in S-shaped canals, including formation of
ledges, zipping, elbow, outer widening, danger zone, perforation and file
deformation. Materials & Methods: Forty S-Shaped canals in resin blocks
were randomly divided into 2 groups of 20 each. Pre-instrumentation images of
the canals were taken via a digital camera and superimposed on images taken
after preparation with TF and K3 systems to apical size of 25/06 and 30/06.
Canal aberrations were measured from the superimposed image at five levels
using AutoCAD system. Fisher exact test and Mann Whitney test were used for
analysis of the data. Results: the incidence of zipping, elbow and apical
transportation was significantly lower in the TF group (P = 0.04). Generally
the incidence of aberration increased when the apical size increased to 30/0.06
regardless of the file system. Significant file deformation was evident in the
TF after single use (P ? 0.001). Conclusion: Under the conditions of this study,
TF manufactured by new technique performed better than K3 systems when used up
to size 25/06 in simulated S-shaped canals. Clinical significance: The
flexibility of thermomechanically treated files is beneficial in canals with
multiple curvatures; however, attention should be paid to the instrument taper
and final apical size of the preparation.