An adaptive system for modifying user brushing action, comprising: a power toothbrush which includes a system for determining the bristle force applied to a user's teeth during brushing action, a processing system for comparing the determined bristle force with several force levels stored within the processing system, and an indication system for communicating information to a user, wherein the processing system is configured to perform the following functional logic steps: determining whether the applied force is in a safe range in which the gums or other tissues are not harmed, and providing an indication that a good amount of force is applied if such is the case, determining whether the applied force is above a threshold value of excessive force, and providing an indication that a harmful amount of force is applied if such is the case, determining whether the applied force has reached a threshold adaptive value of force, which is lower than the threshold value of excessive force, and providing an indication that an intermediate amount of force is applied if such is the case, if the user responds and lowers the bristle force to below the threshold adaptive value of force, providing an indication that a good amount of force is applied, and raising the threshold adaptive value of force from an initial threshold adaptive value when the initial threshold adaptive value is exceeded for a selected number of brushing events, providing an indication that an intermediate amount of force is applied if the actual bristle force goes above the raised threshold adaptive value, and providing an indication that a good amount of force is applied if the actual bristle force goes below the raised threshold adaptive value, and decreasing the threshold adaptive value of force back toward the initial threshold adaptive value when the raised threshold adaptive value is not exceeded for a selected number of brushing events. a power toothbrush which includes a system for determining the bristle force applied to a user's teeth during brushing action, a processing system for comparing the determined bristle force with several force levels stored within the processing system, and an indication system for communicating information to a user, wherein the processing system is configured to perform the following functional logic steps: determining whether the applied force is in a safe range in which the gums or other tissues are not harmed, and providing an indication that a good amount of force is applied if such is the case, determining whether the applied force is above a threshold value of excessive force, and providing an indication that a harmful amount of force is applied if such is the case, determining whether the applied force has reached a threshold adaptive value of force, which is lower than the threshold value of excessive force, and providing an indication that an intermediate amount of force is applied if such is the case, if the user responds and lowers the bristle force to below the threshold adaptive value of force, providing an indication that a good amount of force is applied, and raising the threshold adaptive value of force from an initial threshold adaptive value when the initial threshold adaptive value is exceeded for a selected number of brushing events, providing an indication that an intermediate amount of force is applied if the actual bristle force goes above the raised threshold adaptive value, and providing an indication that a good amount of force is applied if the actual bristle force goes below the raised threshold adaptive value, and decreasing the threshold adaptive value of force back toward the initial threshold adaptive value when the raised threshold adaptive value is not exceeded for a selected number of brushing events. determining whether the applied force is in a safe range in which the gums or other tissues are not harmed, and providing an indication that a good amount of force is applied if such is the case, determining whether the applied force is above a threshold value of excessive force, and providing an indication that a harmful amount of force is applied if such is the case, determining whether the applied force has reached a threshold adaptive value of force, which is lower than the threshold value of excessive force, and providing an indication that an intermediate amount of force is applied if such is the case, if the user responds and lowers the bristle force to below the threshold adaptive value of force, providing an indication that a good amount of force is applied, and raising the threshold adaptive value of force from an initial threshold adaptive value when the initial threshold adaptive value is exceeded for a selected number of brushing events, providing an indication that an intermediate amount of force is applied if the actual bristle force goes above the raised threshold adaptive value, and providing an indication that a good amount of force is applied if the actual bristle force goes below the raised threshold adaptive value, and decreasing the threshold adaptive value of force back toward the initial threshold adaptive value when the raised threshold adaptive value is not exceeded for a selected number of brushing events.