Effects of height and overactivation on a composite nickel-titanium T-loop

The 6-mm-high T-loops produced higher forces, but lower M/F. The conventional protocol produced higher forces and moments. The M/F ratio was similar for both protocols, but overactivation produced a nearly constant M/F throughout deactivation. The use of a 7-mm-high overactivated segmented nickel-titanium loop might improve the performance of orthodontic space closure.