1999, Number 6
Determination of expansion forces and torsion produced in the activation of quad-helix brace in vitro
Parés VFL, Marichi RFJ, Fernández SG
Language: Spanish
References: 37
Page: 215-229
PDF size: 353.97 Kb.
ABSTRACT
At the present work, it determines the expansion forces and torsion of the quad-helix brace, which the fundamental goal was to elaborate tables of expansion forces and torsion based in experiments with four sizes of the quad-helix where it has been produced the basic activations of the same brace to obtain a major knowledge of its behavior and that it could be useful for the clinic control of the force rank in which it developes the action of the quad-helix in the maxillary expansion. It concluded that when the length it is changed the rear bridge of the quad-helix, there is not a lineal variation of the force expansion, as it is shown in the results of the force expansion. Also as it grows the length of the reffering bridge, the strength for milimeter of expansion trends to diminish. About the torsion force, we found that it is not directly proportional to the length of the rear bridge, so that the wire is completely elastic in the torsion movement. At the torque produced by the torsion, we found that the strength of torsion is aproximately proportional to the turning angle for little angles not like this, for angles of 15° or more. At last, we obtained starting from the previous procedures the general formula that gives the force for the quad-helix.REFERENCES