Fracture Resistance of Electropolished Rotary Nickel–Titanium Endodontic Instruments

Irifune

et al. 2014

Journal of Endodontics

Section: Discussionmentioning

confidence: 94%

Section: Discussionmentioning

confidence: 99%

Comparison of Conventional and New-generation Nickel-Titanium Files in Regard to Their Physical Properties

Irifune

et al. 2014

Journal of Endodontics

“…These include the following: anatomy (4), technical aspects like speed and torque (6), clinical skills (7), frequency of instrument re-usage (8,9) and sterilization (10) instrument size (3) and design (11). In addition surface properties may play a role in the fatigue resistance of NiTirotary instruments (12,13).…”

Section: Introductionmentioning

confidence: 99%

The Effect of Electropolishing on Torque and Force During Simulated Root Canal Preparation with ProTaper Shaping Files

Boessler

Paqué

Peters

2009

Journal of Endodontics

The effect of electropolishing on torque and force during simulated root canal preparation with ProTaper shaping files Abstract Surface modifications of nickel-titanium instruments such as electropolishing may reduce fracture incidence but could potentially alter the instruments' mechanical properties. We studied the impact of two surface types, machined and electropolished, of ProTaper shaping files on torque and force during simulated root canal preparation. Pilot holes of 0.5-mm diameter were drilled perpendicularly through 3-mm thick human dentin discs and served as standardized simulated root canals (SSRCs). A total of 300 SSRCs were prepared with ProTaper Sx, S1, and S2 instruments using an automated testing platform. Maximum torque (in Ncm) and maximum force values (in N) were measured. In three experimental groups (Sx, S1, and S2) preparation of SSRCs was performed using electropolished versus machined instruments in the same dentin disc. For all three tested instruments, peak torque was higher for electropolished files; apically exerted forces were similar, except for Sx, in which machined instruments developed higher forces. We conclude that surface treatment by electropolishing alters the cutting ability of nickel-titanium rotary instruments.

The Journal of Contemporary Dental Practice

“…This process is supposed to improve material properties, specifically fatigue and corrosion resistance; however, the evidence is controversial. Some authors 46,47 found an extension of fatigue life for electropolished instruments while most did not. [48][49][50] Moreover, Boessler et al 51 suggested a change in cutting behavior with an increase of torsional load after electropolishing; however, cyclic fatigue was reduced.…”

Section: Surface Treatment Of Niti Alloysmentioning

confidence: 99%

Evolution of Nickel–titanium Alloys in Endodontics

Anil¹,

Neelakantan²,

Nassif³

2017

To improve clinical use of nickel-titanium (NiTi) endodontic rotary instruments by better understanding the alloys that compose them. A large number of engine-driven NiTi shaping instruments already exists on the market and newer generations are being introduced regularly. While emphasis is being put on design and technique, manufacturers are more discreet about alloy characteristics that dictate instrument behavior. Along with design and technique, alloy characteristics of endodontic instruments is one of the main variables affecting clinical performance. Modification in NiTi alloys is numerous and may yield improvements, but also drawbacks. Martensitic instruments seem to display better cyclic fatigue properties at the expense of surface hardness, prompting the need for surface treatments. On the contrary, such surface treatments may improve cutting efficiency but are detrimental to the gain in cyclic fatigue resistance. Although the design of the instrument is vital, it should in no way cloud the importance of the properties of the alloy and how they influence the clinical behavior of NiTi instruments.