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advantage:

1. Take off and wear by yourself, easy to brush;

2. Avoid damage to the periodontal tissue of the tooth;

3. Beautiful, take it off when needed;

4. The structure is simple and the production is easy.

shortcoming:

1. The retention is relatively poor, the effect is not good, and the anchorage is insufficient;

2. The acting force is single, the tooth movement is mostly inclined movement, and the overall movement is difficult;

3. Affect pronunciation;

4. There is a foreign body sensation, it is troublesome to take and wear; 5. It is difficult to deal with the remaining gap.