The growing use of NiTi rotary instruments in dental practice demands a good understanding of their concept of alloy and design in relation to improved properties and inherent limitations. Nickel titanium's super elasticity allows more centered canal preparations with less transportation and a decreased incidence of canal aberrations. Furthermore, the production of files with increased taper be...

OBJECTIVES The aim of this study is to investigate the role of dry cryogenic treatment (CT) temperature and time on the Vickers hardness and wear resistance of new martensitic shape memory (SM) nickel-titanium (NiTi) alloy. The null hypothesis tested was that there is no difference in Vickers hardness and wear resistance between SM NiTi alloys following CT under two soaking temperatures and tim...

Dental alloys as CoCrMo, SS 316L stainless steel and NiTi were electrochemically investigated in artificial Fusayama saliva, unmodified and modified with two different concentrations of natrium fluoride. Electrochemical tests include measurements of open circuit, measurements of linear polarization, potentiodinamic polarization curves and electrochemical impedance spectra. The best electrochemi...

Pronalazak konstrukcije pravoga kuta odrazio se i u građevinarstvu i urbanizmu te limitiranju poljoprivrednih površina. Auktor opisuje nadgrobni spomenik rimskog agrimenzora iz Pompeja i zagonetni nalaz iz Pfiinza. Prihvaća rekonstrukciju pompejanskoga nalaza s tim da se jednonožni stalak radi stabilizacije instrumenta zamijeni tronolnim. Slobodno ovješene vizirne niti nategnute viškovima na vj...

Both the superelastic and the shape memory properties of the cubic NiTi alloy known as Nitinol arise from two-phase transitions; from a simple cubic austenite phase to a trigonal R-phase and to a lower symmetry martensite phase. In this article, we speculate that two competing forces drive these transitions. One is “mechanical” in nature and it takes the cubic austenite structure of NiTi to a d...

The in ̄uences of grain boundaries and relative grain misorientations on stress-induced martensitic transformations in NiTi are studied using unique experiments and ®nite element modeling. Tensile and compressive mechanical tests reveal that polycrystalline NiTi with a dominant <111> ®ber texture and single crystal NiTi oriented along the [111] direction exhibit nearly identical stress±strain cu...

introduction: the purpose of this in vitro study was to compare working length (wl) changes after straight-line access (sla) and different coronal flaring (cf) methods. materials and methods: coronal access preparations were made (without sla) in molar teeth to allow access to 120 canal orifices with a hand file. the suitable cusp and root tips were then flattened to facilitate reproducible and...

introduction: the purpose of this in vitro study was to compare apical microleakage after obturation with nickel-titanium (niti) compared to stainless steel (ss) finger spreaders. materials and methods: eighty straight single-rooted human teeth were instrumented using step-back technique. the specimens were randomly divided into four groups. the two experimental groups (n=30) and the negative c...

In this study, patterned microindents are generated on the surface of NiTi shape memory alloy by laser shock assisted direct imprinting (LSADI). During LSADI, the plasma pressure generated by the laser pulse punches the mask into the target material and thus generates patterned indents. It has been demonstrated that thermally controllable surface pattern can be generated on NiTi surface through...