| 摘要 |
<p>The orthodontic headgear appliance has a safety system which includes a release mechanism for the headgear tensioner, and a system for selectively setting limits for free travel of the facebow. A disconnecting system is activated when a forward force on the facebow is still being applied when the travel limit is reached. A coil spring produces the tensioning forces of the system and is enclosed in a tube. The tube has elongated cutouts which set the limits of travel of the spring.</p> |
