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Self‐ligating appliance (Figure 1.6):

 Developed in 1990.

 Became very popular among non‐extraction orthodontists and was initially used on non‐extraction cases.

 Self‐ligating brackets incorporate a door/clip which ensures full engagement, and holds the archwire in place within the bracket slot.Figure 1.6 Self‐ligating appliance.

 There are two types of self‐ligating bracket:Passive: has a slide mechanism which is passive and places no active force on the archwire.Active: Places an active force on the archwire.

 Once engagement of the archwire has been made by the door/clip, the archwire is free to move in brackets, making the appliance free‐sliding.

 The circumference of the arch is increased, due to space being created on expansion to align teeth, leading to the wide smiles we see today.

 Inter‐arch elastics are used in conjunction with self‐ligating appliances to help improve the patient’s occlusion.

 Self‐ligating appliances are known to reduce chairside time as adjustments are quicker.

 Different types of torque are available within the brackets, such as standard/high/low torque.

 Manufacturers claim that self‐ligating appliances produce lower friction.

Examples of self‐ligating systems:

 Damon® – 3, 3mx, Q, Clear (Ormco Corporation, Orange, CA, USA).

 Clarity™ SL (3M, St Paul, MN, USA).

 Harmony (ASO International, Tokyo, Japan).

 SmartClip™ (3M).

 SPEED System™ (Haspeler Orthodontics, Cambridge, ON, Canada).

 In‐Ovation C® (Dentsply Sirona, Woodbridge, ON, Canada).

Advantages:

 Provides low friction.

 Achieves full archwire engagement.

 Quick and easy to use.

 No elastomeric modules, which makes oral hygiene easier to control.

 Patient can go for longer intervals between appointments.

Disadvantages:

 If there is a fault in the door/clip, it means the whole bracket is faulty, therefore a new bracket would be needed.

 Appliance can be harder to ligate wire; it is important to make sure the wire is fully engaged in the bracket slot for the door to close.

 Higher cost in brackets.

 Difficulty in finishing due to the incomplete expression of the archwires.