GB1412543A - Orthodontic appliance - Google Patents

Abstract

1412543 Orthodontic apparatus M E NORTHCUTT 2 Aug 1973 [1 Nov 1972 15 June 1973] 36756/73 Heading A5R A removable orthodontic appliance, which exerts corrective forces on teeth, includes means for sensing and for recording the amount of time the appliance is in use. Sensing means for actuating the recorder may be responsive to body heat, to capacitance, resistance or other attributes of skin electrolytic functions or to fluids in the mouth, or to a combination of two properties. The recorder may be electronic, or a charging or discharging electric cell, or a small clock. Electrical power, when required, provided by a small battery, the electrolytic activity of the mouth, or spring energy of a headgear. As shown in Fig. 1, headgear comprising an outer bow 14, with coil spring 26, and an inner bow 12, is held in position by an elastic band 20 with a pad 24 which contacts the back of the patient's head, the band 20 being fastened to the hooked ends of outer bow 14 by connectors 22. The inner bow 12 is connected to molars 17 by brackets 16, adjustably mounted on the ends of inner bow 12, whereby the tension of band 20 is transmitted to the patient's teeth. In order to record the time during which the appliance is in use, a clock is actuated by a switch connected to the band. Alternatively, the clock may comprise an integrated circuit which consists of an oscillator, a divider, and a buffer giving an output of lapsed time in code form. The integrated circuit may be controlled by a quartz crystal, supplied by a miniature battery and connected to a "reset" switch. A micro-switch, operated by tension, and possibly also by temperature or pressure, actuates the oscillator as long as the headgear is in use. The total time lapse may be decoded and displayed in digital form. Alternatively, there may be a detachable connection to decoder and display apparatus at a fixed point, e.g. in the orthodontists' office. To discourage tampering, the sensing means may be responsive to tension within a given range of values only.