AIM To compare the rates of orthodontic space closure for: Active ligatures, polyurethane powerchain (Rocky Mountain Orthodontics, RMO Europe, Parc d'Innovation, Rue Geiler de Kaysersberg, 67400 Illkirch-Graffenstaden, Strasbourg, France) and nickel titanium springs. SAMPLE Patients entering the space closure phase of fixed orthodontic treatment attending six orthodontic providers. Twelve pat...

AIM To introduce a new concept, the self-adjusting file (SAF), and discuss its unique features compared with current rotary nickel-titanium file systems. THE NEW CONCEPT The SAF file is hollow and designed as a thin cylindrical nickel-titanium lattice that adapts to the cross-section of the root canal. A single file is used throughout the procedure. It is inserted into a path initially prepar...

BACKGROUND Since the EU Nickel Directive came into force, concern has been raised that palladium may increasingly replace nickel in alloys used in jewellery and dentistry, and that it may cause as many allergy problems as nickel. OBJECTIVES (i) To investigate the clinical relevance of contact allergy to palladium resulting from the wearing of palladium-coated earrings, and (ii) to evaluate th...

The attachment of cells to titanium surfaces is an important phenomenon in the area of clinical implant dentistry. A major consideration in designing implants has been to produce surfaces that promote desirable responses in the cells and tissues. To achieve these requirements, the titanium implant surface can be modified in various ways. This research was designed to elucidate the relationship ...

Prior studies have examined fatigue growth of surface cracks in vacuum to simulate sub-surface growth in Ti-alloys and Ni-base superalloys. Even with the highest vacuum level attained using “state-of-the-art” pumps, it is unclear if conditions of internal crack growth are truly simulated. We consider thermodynamics of the oxidation process to help answer this question. This consideration helps ...

Room temperature monotonic and cyclic stress–strain curves for single crystal and polycrystalline NiTi shape memory alloys containing Ti3Ni4 precipitates are presented. The tensile and compressive single crystal results illustrate the importance of crystallographic texture, the unidirectional nature of the martensitic transformation, and martensite detwinning on tension-compression stress–strai...

K. A. Juggernauth , K. Sun , A. J. Hart , and S. Daly c a Macromolecular Science and Research Center, University of Michigan, 2455 Hayward St, Ann Arbor, MI 48105 b Electron Microbeam Analysis Laboratory, Department of Materials Science and Engineering, University of Michigan, 2455 Hayward St, Ann Arbor, MI 48105 c Department of Mechanical Engineering, University of Michigan, 2350 Hayward St, A...

Technological innovation and the modernization of manufacturing procedures have thoroughly redefined field nickel–titanium (NiTi) rotary reciprocating endodontic instruments [...]

A fundamental understanding of the role of catalysts in dehydrogenation of MgH(2) nanoclusters is provided by carrying out first-principles calculations based on density functional theory. It is shown that the transition metal atoms Ti, V, Fe, and Ni not only lower desorption energies significantly but also continue to attract at least four hydrogen atoms even when the total hydrogen content of...