Orthodontic Assistant Practice Exam

If a bracket is placed too mesially on a lateral anterior tooth, how will the tooth rotate?

1. Facially

2. Mesially

3. Lingually

4. Distally

The correct answer is: Lingually

When a bracket is positioned too mesially on a lateral anterior tooth, it results in an improper force direction applied to the tooth during orthodontic treatment. This malpositioning causes the tooth to rotate away from the direction of the bracket. In this case, since the bracket is placed mesially, the resulting force will push the tooth in a lingual direction. This rotation occurs because the center of resistance of the tooth does not align with the point of force application when the bracket is incorrectly placed. The tooth thus moves or rotates towards the lingual side to counterbalance the inappropriate positioning of the bracket. Understanding this mechanical principle is essential for effective orthodontic treatment, as proper bracket placement is crucial for achieving the desired tooth alignment and overall bite correction.