A toothbrush assembly can include a plurality of bristles and a toothbrush body. The toothbrush body can include an indicator to provide information to a user using the toothbrush during a teeth cleaning session. The indicator can operate independent of any power supply external to the toothbrush assembly. A sensing mechanism can provide an electric signal to the indicator responsive to the user using the toothbrush assembly during the teeth cleaning session. An energy scavenging mechanism can provide operating power to the indicator responsive to the user using the toothbrush assembly during the teeth cleaning session.