A new micro-controller based wear-time monitor for use with removable orthodontic appliances

Removable orthodontic appliances (headgear) are widely used to exert corrective forces on teeth. The rate of corrective movement is a function both of the forces applied and the duration of their application. Subjective statements on headgear wear have been virtually the only source of information on patient compliance with the treatment. Retrospective estimates by patients and parents of the average daily wearing time have commonly served as criteria for both treatment related decisions and scientific research as well as providing rates of co-operation. A system to promote and measure patient compliance with headgear appliances has been developed based on micro-controller and surface mount technology. The first part of the system which is incorporated on the headgear includes a counter/recorder (timer) which is actuated by sensing both body heat and retraction force when the headgear is worn properly by the patient. The second part of the system is a clinic display monitor on which the total accumulated wearing time is displayed for the orthodontist.