Biomechanical Effects of Different Auxiliary-Aligner Designs for the Extrusion of an Upper Central Incisor: A Finite Element Analysis

Table 2

Maximum displacement and loads delivered to the tooth by the different aligners.

	Standard aligner	Rectangular palatal attachment	Rectangular buccal attachment	Ellipsoid buccal attachment
Maximum tooth displacement (mm)	0.079	0.088	0.086	0.092
Fx (N)	0.0	0.4	0.7	0.8
Fy (N)	0.0	−0.2	0.4	0.3
Fz (N)	0.4	2.0	1.3	1.3
Mx (N mm)	1.5	−1.7	2.8	2.9
My (N mm)	1.8	0.6	−1.7	−1.9
Mz (N mm)	−2.8	−1.9	1.0	0.7

“F” represents the force in each direction, and “M” denotes the moment along each direction.