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The Effect of Different Deflection Range and Ligation Methods on the Mechanical Properties of Auxiliary Superelastic Ni-Ti Wires

Author: LinHong
Tutor: LinShan
School: Fujian Medical
Course: Clinical Stomatology
Keywords: Hyperelastic Nickel titanium wire Auxiliary bow
CLC: R783.5
Type: Master's thesis
Year: 2011
Downloads: 17
Quote: 0
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Abstract

Objective: To compare different types of auxiliary bow under the different variables, with a variety of the main arch wire combinations, the the different ligation way mechanical properties (the length of the platform, the platform force value) differences for clinical select a suitable combination of primary and secondary bow reference. Methods: select two sizes of the two manufacturers of nickel titanium wire (0.012inch, 0.014inch), and 3 sizes of the main arch wire combination (0.019 × 0.025 inch SS square wire, 0.018 inch SS round wire and 0.017 × 0.022 inch SS square wire) in 2 different ligation way (pre-formed knot ligation, ligation of the release ligation circle), body bending experiments on the model of the whole arch by Instron universal testing machine to simulate the nickel titanium auxiliary bow correction misplaced maxillary canine is repeated for each combination of test five times, each experiment can be nickel titanium auxiliary bow loading and unloading force - deformation curve. 10 times the power equation fitting the secondary bow unloading curve, to determine platform starting and ending point, and then determine the platform length and platform force. Using factorial analysis methods and the Bonferroni test for statistical analysis to compare a variety of factors of nickel-titanium the secondary bow uninstall stage platform length and platform force. To P lt; 0.05 significance level. Results: 1, four nickel titanium auxiliary bow, with the form of variable increases, the more difficult to demonstrate sustained plateau of the ideal, a certain amount of time required to overcome the increased frictional resistance. 2, the mechanical properties of (1) 0.012inch nickel titanium auxiliary bow, with the form of variable increases (3mm → 4mm), platform length is reduced by an average of 0.2mm, the platform force difference was not significant. (2) 0.014inch nickel titanium auxiliary the bow deformation 3mm → 4mm, the basic platform length constant force value decreased by 20 ~~ 30g; deformation 4mm → 5mm, platform length is reduced by an average of 0.24mm, the force value is essentially the same. (3) in the the forms variables and the main arch wire combinations under the basic length of 0.014 inch nickel titanium auxiliary bow platform and platform force is greater than the of 0.012inch nickel titanium auxiliary bow. 0.012 inch super-elastic nickel titanium auxiliary bow uninstall force average of lt; 80g; 0.014 inch nickel titanium auxiliary bow uninstall the force average value gt; 120g. 3 Advantech EVA Aimeng Di arch wires of two brands of the same basic performance. The archwire 4,0.019 × 0.025inch often as the main archwire preferred. 0.018inch stainless steel main arch wire auxiliary bow combination of most of the nickel-titanium platform length and platform force basic minimum. 5, for the severe dislocation of the teeth, the archwire into the slot produced large deformation will cause the frictional resistance increases and the elastic modulus is decreased. Correction of the beginning of the secondary bow suspension is recommended, but not completely into the slot. Ligation ligation circle, the main arch wire type uninstall force change was not statistically significant. 7, relative to the junction ligation group after the circle ligation ligation 0.014inch IMD nickel titanium auxiliary bow, with the form of variable increases, the plateau significant growth, but the the platform force violent reduced. 8, two deformation via the the ligation circle after ligation 0.014inchIMD nickel titanium wire, uninstall force of approximately 34 ~ 56g. Conclusion: 1, each nickel titanium auxiliary bow, with the form of variables increases, its mechanical properties are weakened trend. 2, under the circumstances, the clinical select 0.012 inch or 0.014 inch nickel titanium auxiliary bow. 3, recommended the use of the 0.019 × 0.025inch SS Fang wire as the main arch wire. 4, the system of primary and secondary bow, the recommended the traditional the ligation circle ligation way.

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