| 摘要 |
This orthodontic appliance comprises a novel arch wire having posterior segments of circular cross-section and an anterior segment at least part of which is rectangular or trapezoidal in cross-section. When used in "light wire" treatment, the arch wire is secured to a bracket by a special lock pin having an offset surface on its tail. The offset surface cooperates with the rectangular portion of the anterior segment to prevent relative rotation between the arch wire and the bracket, thereby allowing torqueing. The special lock pin is also used with a uniform rectangular wire to apply torque to posterior teeth having light wire brackets.
|
