SELF LIGATION www.speedsystem.com 9 How does the SPEED Appliance provide rotational control? When rotational correction is required, SPEED’s Spring Clip is activated upon archwire engagement. Once deflected elastically by the archwire, the Spring Clip provides corrective forces which ensure “full” rotational control. Any subsequent deviation from this ideal is corrected through the re-activation of SPEED’s unique homing action. Side View (Spring Clip Activated) These first-generation SPEED brackets did not have the escape-proof feature which has been incorporated into the design of subsequent generations. Nonetheless, they provided dramatic evidence of their ability to rotate teeth. As observed in the band experiment shown previously (page 7), the bicuspid (above right) has advanced much as the spoke of a locomotive drivewheel advances when it rolls along a rail. However, at this stage, the frictional forces associated with the archwire/ bracket coupling have diminished to near zero so that stretched transeptal fibers can now tow the bicuspids distally into the newly formed spaces if stops are not applied. Spring Clip Activated Top View (Sectioned) Archwire Bracket Spring Clip Corrective Force Ideal Tooth Position Side View (Spring Clip in Home-Position)
RkJQdWJsaXNoZXIy Nzg3Njc4