Edgewise Appliance

Edgewise Appliance

• He deviced a metal bracket having a rectangular slot of 0.022” × 0.028” dimension facing labially.
• Slot received a rectangular arch wire of 0.022” × 0.028” dimension.
• Wire is inserted into the bracket with the narrow dimension placed occluso-gingivally.
• Mode of insertion of the wire is called edgewise and therefore, the technique was called edgewise technique.
• Unique feature of having a rectangular arch wire in a rectangular slot enabled control of tooth movement in all the three planes of space.
• Angle described the use of an ideal arch wire that incorporated certain bends called the fist, second and third order bends.

“Importance of studying the edgewise appliance for better orthodontic outcomes”

• • First order bends: First order bends are those that are made in the horizontal plane, i.e. in and out bends or labiolingual corrections.

• • • These are placed to compensate for differences in the buccolingual prominence of the teeth.
  • Second-order bends: These bends are placed to achieve the correct mesiodistal axial inclination of teeth.

• • • These bends are made in the vertical plane.
    • They are used for anchorage preparation or uprighting teeth.
    • They are also used for the paralleling of roots and elevation or depression of certain teeth.
  • Third-order bends: These are torsion bends. They are placed to get the correct buccolingual position by moving the roots.

• Ability to move teeth in all three planes of space.
• Good control over tooth movement.
• Bodily tooth movement is possible.
• Precise finishing is possible.

• Need to apply heavy forces.
• Need for complex wire bending.
• Increased friction between the archwire and the bracket.
• Need for extraoral forces for anchorage.
• Difficulty to open deep bites.