Aim: To compare the frictional resistance produced by titanium and stainless steel (SS) brackets with various orthodontic wires used in sliding mechanics. To evaluate surface texture of brackets and wires using scanning electron microscopy (SEM). Materials and methods: A total of 40 canine brackets of titanium and SS having 0.022” slot were tested for static and kinetic friction, with SS, low-friction titanium–molybdenum alloy (TMA), timolium and titanium–niobium (Ti–Nb) wires (0.019” × 0.025”), using a universal testing machine. To evaluate the surface roughness, the brackets and wires were subjected to SEM before and after testing. Results: Titanium brackets showed greater mean static and kinetic frictional forces compared to SS brackets with all the wires that were tested. It was lowest with timolium wire followed by SS wire, low-friction TMA and highest with Ti–Nb wire. The SEM indicated greater surface roughness of titanium bracket slot compared to the SS bracket slot, and titanium wires showed greater surface roughness compared to the SS wire. Conclusion: The SS bracket with SS wire would produce efficient results during retraction in sliding mechanics. However, in nickel-sensitive patients where titanium brackets are used as an alternative, the wire of choice would be timolium wire. Low-friction TMA and Ti–Nb wires would be the secondary wires of choice. Clinical significance: Nickel sensitivity and frictional resistance remain a matter of concern during orthodontic treatment for the patients and orthodontist, respectively. This study highlights the orthodontic wire of choice to reduce frictional resistance while using titanium brackets in nickel-sensitive patients.
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