Effects of T-loop geometry on its forces and moments.

ABSTRACT

The moments and forces produced by various orthodontic T-loop spring designs were measured. The effects of dimension changes (within clinically used ranges) and the addition of gable bends with heat treatment were assessed. Increasing the vertical or horizontal dimension reduced the spring's load-deflection rate and its moment-to-force ratio. Gable preactivation with heat treatment had the opposite effects.