Abstract: An extraoral force-reaction device engageable with the wearer's head and/or neck, such as a headcap or a neckband, is connected to an intraoral force-applying device, such as molar bands, by helical spring force-producing means. Snapback of the force-applying means is controlled in response to stressing of the force-producing means beyond a predetermined maximum degree of force exerted by the force-producing means. Snapback control is effected by disconnectible connection means which can be disconnected to interrupt the application to the intraoral means of force capable of moving such intraoral means. The force to be exerted by the spring force-producing means can be readily adjustable in predetermined increments, such as by engaging a spring end hook selectively with any anchor post of several posts arranged in a row lengthwise of the spring.

Abstract: An orthodontic headgear appliance having a safety system which includes force-adjusting mechanism for the headgear tensioning apparatus, a system for selectively setting limits for travel of the facebow during orthodontic treatment and a disconnecting system for disconnecting the facebow from the headgear tensioning apparatus when a forward force on the facebow exceeding a predetermined value continues to be applied after the travel limit is reached.

Abstract: An extraoral force-reaction device engageable with the wearer's head and/or neck, such as a headcap or a neckband, is connected to an intraoral force-applying device, such as molar bands, by force-producing means, such as springs. Snapback of the force-applying means is controlled in response to relative movement of the intraoral means and the extraoral force-reaction means away from each other beyond a predetermined maximum limit, or in response to stressing of the force-producing means beyond a predetermined maximum degree of force exerted by the force-producing means. Snapback control may be effected by latching of a limit latch to prevent or limit return movement of the force-reaction device and the force-applying device, or disconnectible means can be disconnected to interrupt the application to the intraoral means of force capable of moving such intraoral means.

Abstract: An extraoral force-reaction device engageable with the wearer's head and/or neck, such as a headcap or a neckband, is connected to an intraoral force-applying device, such as molar bands, by force-producing means, such as springs. Snapback of the force-applying means is controlled in response to relative movement of the intraoral means and the extraoral force-reaction means away from each other beyond a predetermined maximum limit, or in response to stressing of the force-producing means beyond a predetermined maximum degree of force exerted by the force-producing means. Snapback control may be effected by latching of a limit latch to prevent or limit return movement of the force-reaction device and the force-applying device, or disconnectible means can be disconnected to interrupt the application of primary force to the intraoral means and reaction force to the head or neck engageable means.

Abstract: An extraoral force-reaction device engageable with the wearer's head and/or neck, such as a headcap or a neckband, is connected to an intraoral force-applying device, such as molar bands, by force-producing means, such as springs. Snapback of the force-applying means is restricted by limiting the normal range of movement of the force-applying elements and such snapback is controlled in response to relative movement of the intraoral means and the extraoral force-reaction means away from each other beyond a predetermined maximum limit, or in response to stressing of the force producing means beyond a predetermined maximum degree of force exerted by the force producing means. Snapback control may be effected by latching of a limit latch to prevent or limit return movement of the force-reaction device and the force-applying device, or disconnectible means can be disconnected to interrupt the application of primary force to the intraoral means and reaction force to the head or neck engageable means.

Abstract: An extraoral force-reaction device engageable with the wearer's head and/or neck, such as a headcap or a neckband, is connected to an intraoral force-applying device, such as molar bands, by force-producing means, such as springs. Snapback of the force-applying means is restricted by limiting the normal range of movement of the force-applying elements and such snapback is controlled in response to relative movement of the intraoral means and the extraoral force-reaction means away from each other beyond a predetermined maximum limit, or in response to stressing of the force-producing means beyond a predetermined maximum degree of force exerted by the force-producing means. Snapback control may be effected by latching of a limit latch to prevent or limit return movement of the force-reaction device and the force-applying device, or disconnectible means can be disconnected to interrupt the application of primary force to the intraoral means and reaction force to the head or neck engageable means.

Abstract: Danger of serious injury caused by sharp projections on a displaceable intraoral orthodontic appliance is avoided, or at least greatly decreased, by providing guards alongside such projections or by substituting guards for such projections. Such a guard can be a wire having an enlarged blunt end portion preferably in the form of a loop. The guard wire is mounted alongside the sharp projection of the orthodontic appliance, such as an inner bow anchor tip, and projects beyond such tip. In some instances, the sharp tip, such as a spur, can simply be replaced by a wire having a blunt tip.