Passive self-ligating systems
Passive self-ligating systems differ from active systems in the way that a rigid clip such as a sliding door holds the archwire in place. The clip does not apply any force on the orthodontic archwire and the alignment in the 3 planes of space can only be achieved by using a bigger archwire to fill the slot, which decreases the play between the interface of the archwire and the inside of the slot of the bracket, unlike active self-ligating systems where the clip participates in the repositioning of the archwire at the bottom of the bracket slot.
Example of Damon® Q brackets system.
Initial stage of alignment.
Example of Damon® Clear™ brackets in the maxilla and Damon® Q brackets in the mandible.
Example of Damon® 3. This version of Damon® brackets is no longer available on the market. The clear part of the bracket was made of an acrylic polycarbonate which delaminated itself from the bonding pad.
Passive systems all have a twin bracket design.
The SmartClip™ system differs from other passive systems by the C-shaped clip that opens and closes like lobster claws. The archwire is thus never entirely entrapped by the clip like in a passive or active system. The archwire never being entrapped, it is often necessary to add an elastomeric ligature to hold the archwire in place.
Here is a clinical example of SmartClip™. Notice the width of the bracket (5.1 mm) and the presence of elastomeric ligatures to hold the archwire in place and prevent accidental disengagement. The C-shaped clip is really visible.
Like the majority of bracket systems, the challenge, when a patient undergoes an orthodontic treatment, is to maintain an optimal oral hygiene.