Comparison of First order Loads Deflection Forces of Super-Elastic Nickel Titanium Arch Wires (An In Vitro Study)
Aims: to compare the load-deflection ratios between three groups of super elastics nickel-titanium orthodontic wires from three different manufacturers super elastic 0.012-inch wires.
Materials and Methods: the sample examined were 150 nickel-titanium alloy orthodontic wires commercially available from three different manufacturers (IOS, A-star and DENXY super elastics nickel-titanium 0.012 inch wires ) were tested for load deflections rate, the records were taken with the aid of digital Universal testing machine(compression tension machine), simulating an extrusive force at the right canine (TYPODONT model) , in-activations of 0 to 3 mm, with readings of the force released by deflection in unloading of 0.5mm, starting from 2.5mm, 2mm,1.5mm,1mm, 0.5mm consequently.
Results: statistically significant differences were found among the three wire manufactures concerning the load deflections behaviors illustrate that the least mean of wire deflections recorded for the (A star) wire type then followed by (IOS) wire type and the greatest mean was for the (DENXY) wire (A-star<IOS<DENXY) at unloaded distances in a consequence of 0.5mm.
Conclusion: the comparison of mean load-deflection ratios revealed that (A star) wire has the lowest mean load-deflection ratios while (DENXY) wire has the greatest mean value.