Two artificial teeth were fixed with a distance of 15 mm between the two bracket centers. A straight wire with two different hooks and lengths crimped in the wire next to the bracket was then engaged into the slots. A contractile force was finally applied between the hooks to activate the system with a superelastic Ni-Ti closed spring, which theoretically delivers constant force.Variables that affect this system include LA, LB, C, D1, D2, temperature,and the material characteristics of the wire.
LA, length of the long hook;
LB, length of the short hook;
D1, distance between the two hooks;
D2, distance between long hook and tooth A
orientation of the model corresponding to the x-, y-, and z-axes.
(y) this system can be conceptualized as an asymmetrical V-bend. Since the Vbend is not always used alone in practice, we can also modify and extend this system by incorporating an extra mesiodistal force that generates space closure in sliding mechanics.31 Tooth movement in translation can be achieved by a space close force and a counter moment to prevent tipping. Our new force system can provide the counter moment
” A new orthodontic force system for moment control utilizing the flexibility of common wires: Evaluation of the effect of contractile force and hook length”