Systems and methods for improved engagement between aligners and teeth

3 The method of claim 2 wherein the force receiving component and the force transmitting component are positioned so that the force transmitted to at least one tooth which lags its intended position is increased.

The method of claim 3 wherein the position of the contact point adjusts within the locus of engagement as the force transmitted to the at least one tooth which lags its intended position is increased to establish an equilibrium.

14 The method of claim 3 wherein the force transmitting and force receiving components are arranged to counter a force from a first surface with a force from a second surface.

The method of claim 14 wherein the force from the first surface is an intrusive force and the force from the second surface is an extrusive force.

The method of claim 14 wherein the force from the first surface is an extrusive force and the force from the second surface is an intrusive force.

The method of claim 14 wherein a single attachment device comprises the first surface and the second surface.

The method of claim 14 wherein a first attachment device comprises the first surface and a second attachment device comprises the second surface.

A system for repositioning teeth in a patient jaw, the system comprising:

• an attachment for bonding to a tooth at a pre-selected position, said attachment having at least one force receiving component for receiving a force;
• and
• a polymeric shell repositioning appliance placeable over at least some of the teeth in the patient jaw, the polymeric shell having at least one force transmitting component positioned to engage the force receiving component of the attachment when the attachment at the pre-selected position and the force receiving component engage each other at contact point, wherein a position of the contact point adjusts within the locus of engagement as the tooth is repositioned.

25 The system of claim 24 wherein the force receiving component and the force transmitting component are positioned so that the force transmitted to at least one tooth which lags its intended position is increased.

The system of claim 25 wherein the position of the contact point adjusts within the locus of engagement to establish an equilibrium as the force transmitted to the at least one tooth which lags its intended position is increased.

35 The system of claim 25 wherein the force transmitting and force receiving components are arranged to counter a force from a first surface with a force from a second surface.

The system of claim 35 wherein the force from the first surface is an intrusive force and the force from the second surface is an extrusive force.

The system of claim 35 wherein the force from the first surface is an extrusive force and the force from the second surface is an intrusive force.

The system of claim 35 wherein a single attachment device comprises the first surface and the second surface.

The system of claim 35 wherein a first attachment device comprises the first surface and a second attachment device comprises the second surface.

46 The method of claim 44 wherein the force receiving component and the force transmitting component are positioned so that the force transmitted to at least one tooth which lags its intended position is increased.