Effect of bracket and wire composition on frictional forces

Area of Science:

• Orthodontics and Dental Biomechanics
• Materials Science in Dentistry

Background:

• Previous research focused on single tooth friction along archwires.
• Understanding friction in buccal segment attachments is crucial for effective overjet reduction using sliding mechanics.

Purpose of the Study:

• To investigate and compare frictional forces in buccal segment attachments during overjet reduction.
• To evaluate the influence of different bracket (steel, ceramic) and archwire (steel, nickel titanium, polymeric) materials and dimensions on friction.

Main Methods:

• A buccal segment model was utilized to simulate orthodontic forces.
• Friction was measured using steel and ceramic brackets with steel, nickel titanium, and experimental polymeric wires of varying dimensions.

Main Results:

• Larger dimension rectangular wires and steel wires significantly reduced friction compared to smaller wires and nickel titanium wires.
• Ceramic brackets exhibited higher frictional resistance than steel brackets, particularly with smaller rectangular wires.
• The combined effects of environment, ligation, bracket, and archwire minimized differences between bracket types.

Conclusions:

• Wire choice, specifically larger rectangular dimensions and steel material, is more critical than bracket material (steel vs. ceramic) for minimizing friction in buccal segments during overjet reduction.
• Clinical implications suggest minimal difference between steel and ceramic brackets in buccal segments, emphasizing the importance of appropriate wire selection for tooth displacement.
• The experimental polymeric archwire was found unsuitable for orthodontic use in its current form.