The invention discloses an upper support which comprises a lower jaw support and side supports. The side supports stretch backwards to form rear supports. The two rear supports are directly fixed through a connecting piece and then form a funnel-shaped structure which is completely attached to the head of a user. Due to the fact that the two rear supports are directly fixed through the connecting piece and then form the funnel-shaped structure which is completely attached to the head of the user, the wearing comfort level of the user is improved. Traction force is applied upwards from the small end of the funnel-shaped structure, the force is gathered in the curvature center direction of the side wall through the arc-shaped side wall of the structure, the curvature center is located on the inner side of the wrapped head, upward traction force is applied to the funnel-shaped structure continuously, the traction force provided by a traction device is utilized in a maximum mode, and thus the optimal traction effect is guaranteed.