Copper, Aluminum and Nickel: A New Monocrystalline Orthodontic Alloy

<p><strong>Introduction: </strong>This study was designed to evaluate, via tensile and bend testing, the mechanical properties of a newly-developed monocrystalline orthodontic archwire comprised of a blend of copper, aluminum, and nickel (CuAlNi). <strong>Methods: </strong>The sample was comprised of three shape memory alloys; CuAlNi, copper nickel titanium (CuNiTi), and nickel titanium (NiTi); from various orthodontic manufacturers in both 0.018” round and 0.019” x 0.025” rectangular dimensions. Additional data was gathered for similarly sized stainless steel and beta-titanium archwires as a point of reference for drawing conclusions about the relative properties of the archwires. Measurements of loading and unloading forces were recorded in both tension and deflection testing. Repeated-measure ANOVA (α= 0.05) was used to compare loading and unloading forces across wires and one-way ANOVA (α= 0.05) was used to compare elastic moduli and hysteresis. To identify significant differences, Tukey post-hoc comparisons were performed. <strong>Results: </strong>The modulus of elasticity, deflection forces, and hysteresis profiles of CuAlNi were significantly different than the other superelastic wires tested. In all tests, CuAlNi had a statistically significant lower modulus of elasticity compared to the CuNiTi and NiTi wires (<em>P </em><0.0001). The CuAlNi wire exhibited significantly lower loading and unloading forces than any other wire tested. In round wire tensile tests, loading force at all deflections was significantly lower for CuAlNi than CuNiTi or NiTi (<em>P </em><0.0001). In tensile testing, the CuAlNi alloy was able to recover from a 7 mm extension (10% elongation) without permanent deformation and with little to no loss in force output. In large-deflection bend tests at 4, 5, and 6 mm deflection, CuAlNi showed the significantly lowest loading forces across the three wire materials (<em>P </em><0.0001). The NiTi wires showed up to 12 times the amount of energy loss due to hysteresis compared to CuAlNi. CuAlNi showed a hysteresis loss that was significantly less than any other wire tested in this study (<em>P </em><0.0001). <strong>Conclusions: </strong>The relatively constant force delivered for a long period of time during the deactivation of this wire, the minimal hysteresis loss, the low force output in deflection, and the relatively low modulus of elasticity suggest that CuAlNi wires should be considered an important material addition to orthodontic metallurgy.</p>

Name thesis:degree_name

Master of Science in Orthodontics and Dentofacial Orthopedics (MSODO)

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Orthodontics and Dentofacial Orthopedics

Year

2014

Author dc:creator

• Wierenga, Mark

Contributors dc:contributor

• Leggitt, V. Leroy
• Olson, Gregory
• Rungcharassaeng, Kitichai

• Dentistry
• Orthodontics and Orthodontology
• Orthodontic Wires
• Orthodontic alloys
• Monocrystalline orthodontic alloys
• tensile strength
• archwires

Statement dc:rights

• This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.

Language dc:language

English

Repository record dc:identifier

https://scholarsrepository.llu.edu/etd/195

OAI identifier oai:identifier

oai:scholarsrepository.llu.edu:etd-1176