Patent ID: 8690579

Claim:
A dental zone tracking system for a toothbrush which compensates for head movement during brushing, comprising: a toothbrush which includes a system ( 20 ) for determining the orientation of the toothbrush during brushing by a user; stored target information ( 22 ) for toothbrush orientation for each of a plurality of selected dental zones; a processing system ( 24 ) for comparing the toothbrush orientation information with the target orientation information, once the toothbrush orientation information and the target orientation information are both in the same coordinate system and for determining which, if any, target information matches, within a selected tolerance, the toothbrush orientation information; a compensation system ( 24 ) which produces adjusted target information for the dental zones based on differences between the toothbrush orientation information and previous target information, wherein the compensation system includes using initial head orientation information and wherein the head orientation information is updated by determining the difference between the toothbrush orientation information and the target range orientation information at time intervals; and a feedback system ( 28 ) responsive to the processing system communicating brushing information to the user concerning brushing in the selected dental zones.