How to correct the phenomenon that children cover the sky? Wear an appliance to correct it early. Stomatologist pointed out that the correction of ground cover days can be divided into several periods, among which 2-5 years of ground cover days in defoliation period is the best correction period. Under the guidance of a doctor, the correction can be completed in 3-6 months by simple methods such as wearing movable appliances and correcting bad oral habits. In the permanent tooth stage, 12-13 years old is the golden age for proper correction, which can also achieve ideal correction effect. In addition, it is to correct the child's bad oral habits. In order to better prevent children from being trapped in the sky, correct bad habits such as incorrect breastfeeding posture, jaw extension and finger sucking in time, and check children's teeth regularly can also play a certain preventive role.