In the edgewise appliance, what component enables rotational control through ligature ties?

In the edgewise appliance, what component enables rotational control through ligature ties?

• A. Ligature ties on eyelets
• B. Elastics
• C. Headgear
• D. Clamps

Answer: (A)

Rotational control in the edgewise system comes from how ligature ties cinch the archwire to the bracket via the eyelets. When the ligature is tied around the eyelets in a deliberate pattern, it creates a moment at the bracket–wire interface that twists the tooth about its long axis, producing rotation. Elastics pull teeth together or apart but don’t generate the targeted rotational moment needed for turning a tooth. Headgear provides external anchorage and vertical control, not intra-bracket rotational torque. Clamps secure the wire but don’t create the rotational moment achieved by ligatures on the eyelets.

Rotational control in the edgewise system comes from how ligature ties cinch the archwire to the bracket via the eyelets. When the ligature is tied around the eyelets in a deliberate pattern, it creates a moment at the bracket–wire interface that twists the tooth about its long axis, producing rotation. Elastics pull teeth together or apart but don’t generate the targeted rotational moment needed for turning a tooth. Headgear provides external anchorage and vertical control, not intra-bracket rotational torque. Clamps secure the wire but don’t create the rotational moment achieved by ligatures on the eyelets.