Table 6.

Theoretical torque loss for different square and rectangular archwires in 0.018- and 0.022-in. bracket slots (all with nominal dimensions—based on Dellinger [13])

Wire cross-section	Wire size (in.)	Slot size (in.)	Calculated torque loss (degrees)
Square/rectangular	0.018 × 0.018/0.022/0.025	0.018	0
Square	0.019 × 0.019	0.022	9.96
Rectangular	0.019 × 0.022	0.022	8.37
Rectangular	0.019 × 0.025	0.022	7.24