Refinement influence in the cleaning efficacy of rotary nickel-titanium Mtwo ® instruments in oval-shaped canals by means of optical microscopy.
Loading...
Date
2014-05
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Objective: This study evaluated the cleaning efficacy of the rotary nickel–titanium Mtwo® by
means of optical microscopy in oval‑shaped root canals and compared refinement influence
using ultrasonic files or Hedströem files.
Materials and Methods: Twenty mandibular incisors were accessed, included in epoxy resin
blocks, and cut transversely at 3, 6, and 9 mm from the apex. Teeth were instrumented using
rotary nickel–titanium Mtwo. Digital images of the root cross sections were obtained before and
after instrumentation with a digital camera attached to an optical microscope. Subsequently,
samples were randomly divided into two groups for refinement. Group I was refined using
ultrasonic files #30 and group II with Hedströem files #30. Final digital images of cross sections
after refinement were captured and analyzed. The boundaries for the uninstrumented perimeter
were measured by the software ImageTool 3.0. The data obtained were statistically analyzed by
analysis of variance (ANOVA) and t‑test.
Results: Mtwo instrumentation produced 41.48% of the uninstrumented perimeter. The final
refinement using Hedströem and ultrasonic files decreased the uninstrumented perimeter.
Significant differences (t‑test, P = 0.00) were found at the three thirds after the final refinement,
except for the apical third that was enhanced by Hedströem file. However, there was no statistical
difference between the two refinement techniques used (P > 0.05). Mtwo instrumentation was
not capable of cleaning and shaping the entire perimeter of the root canals walls.
Conclusions: The final refinement, either with ultrasonic files or with Hedströem files, resulted
in significantly less uninstrumented perimeter.
Description
Keywords
Instrumentation, Mtwo® file, nickel–titanium file, oval canal, refinement
Citation
Pontes Cibella Maymone, Sassone Luciana Moura, Murad Cristiana Francescutti, Fidel Rivail Antônio Sérgio, Vilhena Fernando Sili. Refinement influence in the cleaning efficacy of rotary nickel-titanium Mtwo ® instruments in oval-shaped canals by means of optical microscopy. Indian Journal of Dental Research. 2014 May-Jun; 25(3): 279-283.