Evaluation of palatal arches made from low-nickel stainless steel wire

Aim: To test the hypothesis that there is no difference between stainless steel wires and low-nickel stainless steel ones regarding their mechanical behavior. Force, resilience and elasticity modulus produced by Coffin, “W” arch, and Quad-helix appliances made of 0.032-inch and 0.036-inch wires were evaluated.
Methods: Fifteen appliances of each type (Coffin, "W" arch, and Quad-helix) were made according to metal alloy and wire thickness. All arches (12 groups of 15 appliances each) were submitted to mechanical compression test by using an EMIC DL-10000 machine simulating activations of 5, 8, 10, and 12 mm. Analysis of variance with multiple comparisons and Tukey’s test were used (P < 0.05) for analyzing statistically force and resilience data.
Results: The results showed that mechanical properties depended on shape of the appliance, diameter of the wire, amount of activation, and metal alloy.
Conclusions: Appliances made from lownickel stainless steel alloy had higher release of force, resilience and elasticity modulus compared to those made of stainless steel alloy.