The aim of this study was to evaluate deflection forces of orthodontic wires of different alloys engaged into conventional brackets using several ligation types. Stainless steel, conventional superelastic nickel-titanium and thermally activated nickel-titanium archwires tied into conventional brackets by a ring-shaped elastomeric ligature (RSEL), a 8-shaped elastomeric ligature (8SEL) and a met...

AIM The aim of the present study was to compare the resistance to cyclic fatigue of Hyflex® (Coltene-Whaledent, Allstatten, Switzerland) size 40 taper.04 nickel titanium instruments used in continuous rotation versus the use with a reciprocating motion. The null hypothesis was that different file motions had no influence on the lifetime of instruments subjected to a cyclic fatigue test. METHO...

The aim of this study was to evaluate, in vitro, frictional forces produced by ceramic brackets and arch wires of different alloys. Frictional tests were performed on three ceramic brackets: monocrystalline (Inspire ICE), polycrystalline (InVu), polycrystalline with metal slot (Clarity), and one stainless steel bracket (Dyna-Lock). Thirty brackets of each were tested, all with .022' slots, in c...

AIM This in vitro study measured the force-deflection behavior of selected initial alignment archwires by conducting three-point bending tests under controlled conditions. The study tested four wire designs: multistranded stainless steel, conventional stainless steel, superelastic nickel-titanium, and thermoactivated nickel-titanium archwires. METHOD The wires (n = 15) were ligated into stain...

OBJECTIVE To compare the disinfecting efficacy of the sodium hypochlorite irrigation by root canal preparation with stainless steel hand files, taper 0.02 and nickel-titanium Mtwo files with taper 0.04-0.06. STUDY DESIGN 40 extracted human teeth were sterilized, and then inoculated with Enterococcus faecalis (ATCC 29212). After 6 day incubation time the root canals were prepared by hand with ...

OBJECTIVES/HYPOTHESIS To investigate and treat the late complications of using nickel-titanium alloy stents in laryngotracheal, bronchial, and esophageal stenosis patients who developed severe laryngotracheal stenosis (SLS). STUDY DESIGN Retrospective clinical study. METHODS Thirteen patients with SLS or tracheoesophageal fistula secondary to insertion of a nickel-titanium alloy stent for t...

introduction: rotary nickel-titanium (niti) instruments are thought to allow shaping of narrow, curved root canals more efficiently and more effectively than stainless steel hand instruments. however, the continued search for even more effective and safer instruments has resulted in new rotary systems being introduced on a regular basis. the aim of this study was to compare shaping parameters o...

objectives: the purpose of this study was to evaluate the resistance to fatigue failure of five different nickel-titanium rotary files in three different curved trajectories. materials and methods: a total of 150 neoniti a1, race 25.06, mtwo 25.06, twisted file 25.06 and protaper next x2 files with the tip size of 25 were tested (n=30 for each group). three groove types simulating curved canals...

background and aim: the purpose of this study was to evaluate the effect of autoclave sterilization on the fracture rate of protaper instruments (ex vivo). materials and methods: one hundred shaping and finishing protaper instruments were used in a crown – down technique for cleaning and shaping the mesial canals of extracted mandibular molars using 5.25% naocl for irrigation. in the experiment...

and porcelain-fused-to-metal restorations instead of gold or silver alloys. This tendency seems to be the same a]1 over the world, However, the expanded use of nickel-containing base metal alloys in dentistry has raised questions concerning their biological s fety, namely, carcinogenic and sensitivity risks.i) On the other hand, since pure titanium or titanium-based alloys have excellent biocom...