Shaping ability of three rotary NiTi system : Mtwo, K3, proTaper, in simulated curved canals (Part 2)‎

Abstract EN

Background: Part II of this study'was performed to document the incidence of canal aberrations (apical zipping associated with elbow, ledge and perforation).

Changes.of working length, preparation time for each system and the instruments fracture, in simulated curved canals.

Materials and methods: Seventy five simulated curved canals of 40° curvature were divided into three groups and » prepared to an apical size 30 using a single length technique for Mtwo and a crown-down technique for K3 and ! ProTaper instruments.

Canal aberrations, changes of working length, time of preparation and instruments fracture were evaluated.

The measurements were carried out at five different levels.

Pre-and postoperative images of the canals were taken at 40X magnification.

The canal shape was assessed using Photoshop CS2 soft ware.

Statistical analysis of the results- was done using ANOVA and Student's t-test at 5% significant level.

Results: More zips associated with elbow were created with ProTaper followed by K3; using Mtwo no aberration were resulted.

In term of working length changes, no significant differerences were detected between the three rotary systems.

The shortest time for instrumentation was achieved with Mtwo system and the longest time for ProTaper system.

Four ProTapers instruments (9.52%) were separated, while neither Mtwo nor K3 were fructured.

Conclusions: Canals prepared with PT showed more incidences of canal aberrations than K3, while Mtwo instruments scored no aberrations.

All tested systems prepared the canals without substantial changes in working length.

Mtwo prepared the canals faster than the other tested instruments.