This article covers the following topics:
- The different types of tooth movements in clear aligner treatment; crown tipping, root tipping, torquing, rotation, translation, extrusion, intrusion
- The predictability of tooth movements in clear aligner treatment, including; predictable, moderate and unpredictable/difficult tooth movements
We use these terms to describe the movements of teeth during clear aligner treatment.
Our case parameters describe how much movement we recommend for each of these types of movements.
Crown tipping is the tilting of the crown of a tooth without moving the apex of the root.
Root tipping is tilting the root of the tooth without moving the apex of the crown.
Torquing The definition of torque has evolved from fixed appliances and although there is no wire and bracket, the concept remains the same with clear aligners. In clear aligner therapy, to torque a tooth is to move the tooth buccolingually around the centerpoint, so the crown and root move in opposite directions. It is the twisting force which is traditionally required to adjust the inclination of a crown.
Rotation is turning a tooth about its long axis.
Translation is shifting the tooth along the occlusal plane without changing the orientation of the long axis.
Extrusion is moving a tooth out of the supporting structures.
Intrusion is moving a tooth into the supporting structures.
Distalization is moving a tooth along the occlusal plane away from the midline.
Mesialization is moving a tooth along the occlusal plane towards the midline.
Expansion is moving posterior teeth outwards away from the midline.
Proclination is tipping the crown of anterior teeth labially.
Lingualization is moving teeth towards the tongue side of the arch.