[Evaluation of super-elasticity characteristics of orthodontic Ni-Ti alloy wire].
Mechanical properties of orthodontic Ni-Ti alloy wires, especially their super-elasticity characteristics, were investigated in order to use them effectively in the clinics. In this study, twenty commercial orthodontic Ni-Ti wires were tested and two parameters were devised for the load-deflection curve and introduced to evaluate the practical mechanical properties, one being the "super-elastic index: SEI" for super-elasticity, and the other being the "E-load" for the load in the super-elastic region. There was a "flat area" in the load-deflection curve of the super-elastic type of Ni-Ti alloy wires, whose SEI was above seventy and a continuous force could be used through the wide range of deflection. The load of the work-hardened type of Ni-Ti wires, SEI below thirty, was nearly proportional to the deflection. And the middle type showed intermediate properties of the two. The E-load values of the super-elastic type wires are thought to indicate the load level in the super-elastic region. The quantitative evaluation of the super-elasticity characteristics of the orthodontic Ni-Ti wires became possible by the introduction of these parameters.
Yoneyama
T
T
Doi
H
H
Hamanaka
H
H
Noda
T
T
Okamoto
Y
Y
Karibe
M
M
Mogi
M
M
Miura
F
F
D003722:Dental Alloys; D004548:Elasticity; D009532:Nickel; D009967:Orthodontic Appliances; D009969:Orthodontic Wires; D014025:Titanium
D003722:Dental Alloys; D009532:Nickel; D014025:Titanium