Frictional forces when rectangular guiding arches with varying edge bevel are employed

Area of Science:

• Orthodontic biomechanics
• Dental materials science

Background:

• Rectangular wires are standard for 3D tooth movement in orthodontics.
• Edge-beveled wires aim to enhance sliding mechanics and patient comfort.
• Friction significantly impacts the efficiency of orthodontic tooth movement.

Purpose of the Study:

• To evaluate the effect of varying wire edge rounding on canine retraction friction.
• To quantify the impact of wire design on sliding mechanics in orthodontics.

Main Methods:

• Tested 0.016" x 0.022" steel wires (Remaloy, Remanium) in a 0.018" slot system.
• Measured friction-induced force loss during canine retraction using the Orthodontic Measurement and Simulation System (OMSS).
• Compared standard, moderately rounded, and sharply beveled wire configurations.

Main Results:

• Frictional force loss averaged approximately 50% during arch-guided canine distalization.
• Rounded wires significantly reduced friction compared to sharp-edged wires.
• Moderate rounding decreased frictional losses by about 10%; excessive beveling did not improve mechanics and risked leveling loss.

Conclusions:

• Wire edge rounding is a critical factor in optimizing sliding mechanics during orthodontic canine retraction.
• Moderate rounding effectively reduces friction, enhancing treatment efficiency.
• Excessive edge beveling offers no additional benefit and may negatively impact leveling.