According to the regulations of the public health network, the scars of hands and elbows should not exceed 3 cm, and the scars of face and neck should not exceed 2 cm. Laser scar removal technology is mature, and there are scars on the body, which can be repaired by laser technology. Small scars can be repaired to a level close to normal skin, but this method is not suitable for repairing large scars.