FLEXURAL PROPERTIES OF PREMIUM VERSUS INEXPENSIVE NICKEL-TITANIUM ORTHODONTIC ARCHWIRES: AN IN VITRO COMPARISON
Date of Award
Summer 7-14-2026
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Dentistry
First Advisor
David Berzins
Second Advisor
Dawei Liu
Third Advisor
William Lobb
Abstract
ABSTRACT FLEXURAL PROPERTIES OF PREMIUM VERSUS INEXPENSIVE NICKEL-TITANIUM ORTHODONTIC ARCHWIRES: AN IN VITRO COMPARISON Cameron Young, D.D.S Marquette University, 2026 Objective: To analyze differences in flexural properties of thermal and superelastic nickel titanium wires by comparing premium wires manufactured by Ormco and Solventum (formerly 3M) to less expensive alternative wires using a standard three-point bend test. Methods: Nickel-titanium wires from five different manufacturers were tested and categorized as either “premium” (Orcmo, Solventum/3M Unitek) or “inexpensive” (AZDENT, Cx Orthodontic Supply, JMU Dental). A superelastic (SE) and a heat-activated (HA) version of each NiTi wire were included. Fifteen samples were prepared for each of the NiTi wire categories for a total of 150 samples. A three-point bend test was performed for each sample. Tests were run utilizing the following parameters: 14 mm wire span between supports, symmetric deflection with centrally placed indenter/central beam centered at 7 mm, and crosshead rate of 2 mm/min. All parameters meet ISO 15841 standards except for the 14 mm support-support span due to fixture limitations. All wires tested at intraoral temperature (37 1 C). Force values were recorded at each of the following deflection points in activation and deactivation: 1.0 mm, 2.0 mm, and 3.0 mm. Raw data was captured on a computer and converted to an Excel file for analysis. Wire stiffness and force values calculated. One-way ANOVA was performed to compare group means. Variances analyzed with Levene’s Test to compare the consistency of each wire brand. Dunnett T3 post hoc test performed due to unequal variances. Bonferroni correction applied and significance threshold changed to p < .005 to account for repeated pairwise comparisons. Results: All 10 wire groups were statistically different in all variables tested (p < .001). Premium HA wires showed significantly greater stiffness and force than all three inexpensive HA wires. SE wires showed significantly greater stiffness, modulus, and force than HA wires at every deflection point measured (p < .001). Cx Orthodontic HA showed significantly greater variance in activation stiffness, modulus, and force at 1 mm than both premium HA references (p < .005) Variance differences among SE wires were limited to isolated variables. Conclusions: Premium NiTi wires were not consistently superior to the inexpensive alternatives. Among SE NiTi wires in particular, the cost category did not consistently correlate with the mean flexural performance. However, several inexpensive HA wires showed significantly greater variance when pairwise comparisons were performed with its premium wire counterparts. This higher variance suggests manufacturer quality control is more likely a main factor in distinguishing premium and inexpensive NiTi wires.