Rogério Lacerda dos Santos & Matheus Melo Pithon


The emergence of stainless steel wire made of low-nickel content was a major breakthrough in the orthodontic, supplying the need for orthodontics patients who may have hypersensitivity by this ion, but do not know much about the mechanical properties of these wires. The objective of this study is to test the hypothesis that there is no difference between stainless steel wires and low-nickel stainless steel ones regarding their mechanical behaviour. Force, resilience, and elasticity modulus produced by Coffin appliances made of 0.032-inch and 0.036-inch wires were evaluated. Sixty appliances Coffin were made, thirty for each type of alloy being fifteen for each wire thickness. All the arches were submitted to mechanical compression test by using an EMIC DL-10000 machine simulating activations of 4, 6, 9, and 12 mm. Analysis of variance (ANOVA) with multiple comparisons and Tukey’s test were employed (p< 0.05) for assessing force, resilience, and elasticity modulus. The groups using the 0.036 inch presented statistically (p<0.05) higher levels of force, resiliency and elasticity modulus when compared to the arches using the 0.032 inch wire for both alloys. The Coffin appliances for both alloys evaluated can produce adequate forces for orthodontic treatment as long as their clinical application is correctly planned. KEY WORDS: cross-bite, orthodontic appliances, force, nickel allergy.

How to cite this article

DOS SANTOS, R. L. & PITHON, M. M. Coffin Appliance: Study of 2 different types of metal alloys. Int. J. Odontostomat., 4(2):133-137, 2010.