Effects of Attachment Orientation and Designed Vertical Movement on Molar Distalisation With Clear Aligners: A Biomechanical Finite Element Study

Attachment orientation significantly affects the effectiveness of molar distalisation and vertical movement with clear aligners. The 90° attachment group achieved the most effective molar distalisation. The 135° attachment is more effective under intrusive force, while the 45° attachment is preferable under extrusive force.