US Patent 8651857 Dental appliance

A dental appliance for correcting tooth alignment. The appliance includes a body for seating on an arch of teeth. The body is at least partially elastically deformable and has a seated condition into which it is elastically deformable to be seated on an arch of teeth. The body is constructed, when seated on an arch of teeth, for applying, by virtue of said elastic deformation, a correction force on one or more misaligned teeth, at or adjacent a base of the crown of each misaligned tooth, in a direction in which each misaligned tooth is to be moved to correct its alignment.