scholarly journals Superelasticity and force plateau of nickel-titanium springs: an in vitro study

2016 ◽  
Vol 21 (3) ◽  
pp. 46-55 ◽  
Author(s):  
Camila Ivini Viana Vieira ◽  
Sergei Godeiro Fernandes Rabelo Caldas ◽  
Lídia Parsekian Martins ◽  
Renato Parsekian Martins
Keyword(s):  
Analysis Of Variance ◽  
In Vitro Study ◽  
Nickel Titanium ◽  
Vitro Study ◽  
Lack Of Information ◽  
Activation Force ◽  
Post Hoc

abstract Objective: This paper analyzed whether nickel-titanium closed coil springs (NTCCS) have a different superelastic (SE) behavior according to activation and whether their force plateau corresponds to that informed by the manufacturer. Methods: A total of 160 springs were divided into 16 subgroups according to their features and activated proportionally to the length of the extensible part (NiTi) of the spring (Y). The force values measured were analyzed to determine SE rates and force plateaus, which were mathematically calculated. These plateaus were compared to those informed by the manufacturer. Analysis of variance was accomplished followed by Tukey post-hoc test to detect and analyze differences between groups. Results: All subgroups were SE at the activation of 400% of Y length, except for: subgroups 4B and 3A, which were SE at 300%; subgroups 4E and 4G, which were SE at 500%; and subgroup 3C, which was SE at 600%. Subgroup 3B did not show a SE behavior. Force plateaus depended on activation and, in some subgroups and some activations, were similar to the force informed. Conclusions: Most of the springs showed SE behavior at 400% of activation. Force plateaus are difficult to compare due to lack of information provided by manufacturers.

scholarly journals Deformation of nickel-titanium closed coil springs: an in vitro study

2017 ◽  
Vol 22 (1) ◽  
pp. 38-46 ◽  
Author(s):  
Camilla Ivini Viana Vieira ◽  
José Maurício dos Santos Nunes Reis ◽  
Luiz Geraldo Vaz ◽  
Lídia Parsekian Martins ◽  
Renato Parsekian Martins
Keyword(s):  
Analysis Of Variance ◽  
In Vitro Study ◽  
Nickel Titanium ◽  
Vitro Study ◽  
Effective Length ◽  
Test Results ◽  
Post Hoc ◽  
Similar Deformation

ABSTRACT Objective: The aim of this paper was to determine the amount of deformation in four commercial brands of nickel-titanium closed springs. Methods: A total of 130 springs were divided into 13 subgroups, according to their features and manufacturers (Morelli, Orthometric, Ormco and GAC) and activated from 100% to 1000% of the effective length of the nickel-titanium portion present at the spring, at 37 °C. Deactivation data were plotted and deformation was found graphically. The values were compared by analysis of variance and Tukey's post-hoc test. Results: Springs manufactured by Morelli had the same amount of deformation when they were activated up to 700% of Y activation; springs by Orthometric had the same amount of deformation up to 600-700% of Y; springs by Ormco had the same amount of deformation up to 700-800% of Y; and finally, the majority of springs by GAC had similar deformation up to 800%-1000% of activation. All springs tested could be activated up to 700% without rupture. Conclusions: Most subgroups were similarly deformed up to 700% of activation, without rupture of springs. Subgroups 4B, 4C, 4D and 4E showed the same amount of deformation up to 1000% of activation without any rupture at all.

scholarly journals The resistance to axial dislodgement of nickel titanium compression arch wire hooks - an in vitro study

2021 ◽  
Vol 35 (1) ◽  
pp. 21-26
Author(s):  
Agneta Linder-Aronson Karsten ◽  
Carl-Magnus Forsberg ◽  
Martin Öberg
Keyword(s):  
In Vitro Study ◽  
Nickel Titanium ◽  
Vitro Study

scholarly journals The Effect of Glaze Coating on Wear Resistance of Some Acrylic Denture Teeth: An In Vitro Study

2021 ◽  
Vol 13 (2) ◽  
pp. 47-51
Author(s):  
Samaneh Abbasi ◽  
Soodabe Ebrahimi ◽  
Arash Shisheian ◽  
Maryam Farhadian
Keyword(s):  
Wear Resistance ◽  
In Vitro Study ◽  
Resistance Rate ◽  
Vitro Study ◽  
Wear Rates ◽  
Denture Teeth ◽  
Significant Difference ◽  
The Mean ◽  
Post Hoc

Background: Acrylic resin teeth wear resistance has an important role in the denture longevity. This study aimed to clarify the effect of glaze coating on wear resistance of three types of artificial acrylic teeth. Methods: In this in vitro study, the wear resistance rate of three of acrylic denture teeth (GENIUS, STON and CLASSIC) was compared with Ivoclar teeth (n=25/group). The wear resistance was measured by estimating the weight loss in pre and post removing glaze coating, following 5000 cycles in the chewing simulator device. Data analysis was made using paired t test, one-way ANOVA and Tukey’s post hoc test. Results: ANOVA test showed that there was no significant difference between the mean amount of wear of GENIUS, CLASSIC, STON and IVOCLAR teeth in the first stage (P <0.061), but this difference was significant (P <0.001) in the second stage. The result of Tukey post hoc test showed that wear rates of GENIUS were significantly lower than other groups (P<0.001). Comparison between the mean wear rates of each dental group at the first and second stages showed a significant difference between average teeth wear resistance of CLASSIC, STON and IVOCLAR in the first and second stages (P <0.001). Conclusions: In conclusion, the teeth wear resistance of STON and CLASSIC were similar to IVOCLAR. Also, after removing the glaze coating, the teeth wear resistance decreased in all groups but was not statistically significant for group GENIUS.

Effect of Fluoride Prophylactic Agents on the Mechanical Properties of Nickel-Titanium Wires: An in vitro Study

2011 ◽  
Vol 45 (4_suppl1) ◽  
pp. 237-242
Author(s):  
SR Harish Koushik ◽  
Nikhilanand Hegde ◽  
Vinay Reddy ◽  
CM Mahesh ◽  
BS Chandrashekar ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
In Vitro Study ◽  
Nickel Titanium ◽  
Vitro Study

scholarly journals The potential effect of instrumentation with different nickel titanium rotary systems on dentinal crack formation—An in vitro study

PLoS ONE ◽  
2020 ◽  
Vol 15 (9) ◽  
pp. e0238790
Author(s):  
Márk Fráter ◽  
András Jakab ◽  
Gábor Braunitzer ◽  
Zsolt Tóth ◽  
Katalin Nagy
Keyword(s):  
Crack Formation ◽  
In Vitro Study ◽  
Potential Effect ◽  
Nickel Titanium ◽  
Vitro Study
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