Comparison of manufacturer tolerance of different performed orthodontic arch wires

Abstract

Objective: To measure manufacturer tolerance of preformed rectangular orthodontic arch wires in terms of cross sectional, vertical and transverse dimensions.

Materials and Methods: One hundred and twenty preformed archwires were selected from six various brands in both stainless steel and nickel titanium. Transverse dimensions were measured at both intercanine and intermolar area by photocopying the wires and intra brand comparison was done by using portable USB microscope. Cross sectional dimensions were measured with micrometer while vertical discrepancy was measured at anterior and intermolar region with leaf gauges. One sample t test used to evaluate intra-brand tolerance in wires.

Results: Db orthodontics stainless steel wires were the most oversized while Dentaurum nickel titanium wires were the most undersized in terms of wires height. In terms of wire width, Ortho Organizers stainless steel wires were most oversized while Db orthodontics nickel titanium wires were the most under sized wires. Considering transverse dimension, intercanine width within a brand was found uniform while 3M stainless steel and Dentaurum nickel titanium wires showed statistically significant discrepancy at intermolar area in intrabrand comparison. Statistically significant vertical discrepancy at intermolar region was found in four out of six brands of stainless steel wires and only one brand of nickel titanium wires.

Conclusion: Preformed orthodontic wires can be oversized or undersized in cross sectional dimensions with vertical discrepancy mostly present in stainless steel wires. Manufacturer makes uniform intercanine width but intermolar width is usually expanded from the intended arch form.