To provide an oral tissue treatment device, etc., to be installed and used within the oral cavity for the treatment of oral tissues utilizing patient's occlusion force.

The oral tissue treatment device 1 is installed within the oral cavity at least in part. The device 1 includes a piezoelectric element 2. The piezoelectric element 2 produces electric power (generates electricity) using the patient's occlusion force. The device makes the treatment of oral tissues by using electric power thus generated, or promotes the cure of oral tissue diseases using magnetic force or ultrasonic waves caused via this electric power.