The ultrasound cannon is a medical device that utilizes ultrasound technology for treatment, which can be used for pain management, muscle relaxation, and promoting blood circulation. By generating high-frequency acoustic vibrations, the ultrasound gun is able to penetrate the deep tissues of the human body and provide effective treatment for painful areas. With the advantages of non-invasiveness, no side effects and easy operation, ultrasound gun is widely used in the field of rehabilitation medicine. In contrast, youth brace is an instrument used for orthodontic treatment, which needs to be installed and adjusted in the oral cavity, which is a cumbersome process and may cause discomfort. Therefore, all things considered, the ultrasonic gun is better.