Weeks 2-3 CE Quiz – Biomechanical considerations of moving teeth with plastic (Forum 12) Copy

The wagon wheel effect, described in Andrews six keys of occlusion as a phenomenon of mesial root tip during torque expression of anterior teeth, does not happen with tooth movement via aligners.

For adult orthodontic treatment, the Invisalign software system takes into account attachment design for expansion of the posterior segment to prevent crowns from tipping.

Optimized root control attachments generally have sufficient gingival push surface areas needed for extrusion.

One of the best ways to control root tip when an attachment for root tip is not triggered is to open interproximal space around the tooth for a full wrap of plastic during the movement.

The Invisalign software currently has optimized attachments to help control significant root tip.

Considerations when it comes to pushing vectors of force on a tooth include:

It’s ok and well tolerated for interproximal binding to occur when resolving crowding?

The threshold amount of second order movement of the apex to be considered as a guideline when designing attachments is:

For mesial molar movement greater than 2mm, creating a center of rotation within the clinical crown is best accomplished with what type of attachment?

When developing the transverse arch form, it is useful to apply several degrees of labial root torque to the teeth moving to prevent plunging palatal cusps.

The Extrusion of anterior teeth is best accomplished by:

For controlling torque during anterior space closure, it is best to have attachments on both labial and lingual surfaces.

Tipping, being an easy movement, has no clinical side effects and thus does not need to be accounted for (ie, no overtreatments are needed in the software).