Shaping Ability of Superelastic and Controlled Memory Nickel-Titanium File Systems: An In Vitro Study

Abstract

Improvements in the thermomechanical processing procedures of NiTi wires have led to the development of new NiTi instruments that compose mainly of martensite crystals, making the wire stable at clinical condition. This study aimed at comparing the shaping ability of two rotary nickel-titanium systems manufactured from different NiTi wires. Twenty simulated root canals each with a curvature of 35° in resin blocks were divided into two groups of 10 canals each. Canals in the first group were prepared with superelastic F360 instruments (Gebr. Brasseler, Germany) while canals in the second group were prepared using controlled memory HyFlex®CM™ instruments (Coltène Whaledent, Switzerland). Images were taken before canal preparation and after the use of each instrument. The assessment of the canal shapes was accomplished with a computer image analysis program. Data were statistically analyzed using SPSS program. Within the limitation of this in vitro study, HyFlex®CM™ instruments remained better centered in the apical third of the canals. In most canal segments, no significant differences were observed between either system in the amount of material removed. Both systems were comparable to each other in regards to their ability to enlarge root canal in the same way without procedural errors.

Comparative evaluation of stress distribution against the root canal wall at three different levels using novel NiTi rotary files – A finite element analysis

“…Due to this, they may continue to be in the austenite phase while being employed in a clinical setting, causing an uneven distribution of stress while recovering their form after instrumentation. The findings of this experiment agree with those of Ba-Hattab and Pahncke,[ 32 ] who investigated the shaping capability of the F360 file with different NiTi rotary file systems made from different metallurgy, and they found that the F360 file caused the root canal walls to be under inconsistent amounts of stress. In addition, the S-shaped cross-section of the F360 files may have put extra stress on the dentinal wall.…”

The Impact of Multiple Autoclave Cycles on the Surface Roughness of Thermally Treated Nickel-Titanium Endodontic Files

“…e thermal treatment employed in manufacturing NiTi les enhances their mechanical properties [7]. However, the mechanical properties may be negatively or positively affected by heat generated during the sterilization process [8][9][10].…”

Shaping Ability of a Novel Rotary Nickel Titanium System using Cone Beam Computed Tomography (An Invitro Study)

“…Historically, a range of techniques were employed to assess canal's amount of transportaion, the remainder of remaining thickness of dentinal material, and centering ability. These included the utilization of radiographic methods (9) , the meticulous process of serial sectioning (19) , visual evaluations through photography (20) , intricate observations using scanning electron microscopy (21) , and the application of computer manipulation techniques (22) . However, these methods had inherent invasiveness and posed challenges in accurately repositioning specimens before and after instrumentation.…”