In our daily life, we often see that many people have misaligned upper teeth, small chin, retrusion, long face, facial asymmetry, and other problems. In medical terms, we would call these problems “malocclusion”. First of all, let’s understand what is “malocclusion”: malocclusion is often referred to as “malocclusion” in clinical practice, which refers to children’s teeth, jaws, craniofacial deformities caused by congenital genetic factors or acquired environmental factors during the process of growth and development. It is a malformation of the teeth, jaws, and craniofacial area. In simple terms, it is an abnormality caused by an incongruity in the size, shape, and position of our teeth, the bones that house our teeth, and the bones that support the basic contours of our face. The incidence of malocclusion in modern humans has exceeded 50% and is on the rise. It is important to know that malocclusion does not only affect the aesthetics, but also has a great impact on the maintenance of oral hygiene, the function of the oral and jaw systems, physical growth and development, mental health, school work and life. Since malocclusion develops during the growth and development of children, it is becoming more and more important for parents to pay attention and concern. We parents can learn more about the causes of malocclusion, which will have a positive effect on the growth and development of the child and the orthodontic outcome. Let us briefly understand what factors lead to the occurrence of malocclusion in children at various stages of growth and development. 1, genetic factors The first is the genetic factor is actually very understandable, that is, who the child like who, in our country genetic factors in the cause of malocclusion accounted for about 29%. Early diagnosis – plan – appropriate orthodontic appliances – effect maintenance – follow up. The genetic cause of malocclusion is difficult to correct, the course of treatment is long, serious cases also need surgery, should strive for early and clear diagnosis, and to develop a detailed long-term treatment plan, the choice of suitable orthodontic appliances, after correction requires a longer period of effect maintenance and follow-up. Therefore, parents of families with a genetic history of jaw deformities such as geodesic, small chin, need to pay special attention to this type of child more observation, early treatment, thereby reducing the difficulty and pain of treatment after adulthood. 2, fetal period “congenital malocclusion” The second factor is the fetal period, the mother’s disease, receiving excessive radiation and trauma, etc., can lead to fetal congenital malocclusion, such as life often heard of cleft lip and palate, enamel hypoplasia, multiple teeth, etc. are directly related to this period. 3, breastfeeding period The third factor is that after the birth of the child, artificial breastfeeding bottle position and rubber nipple size is not appropriate, and feeding posture is not correct, etc. can cause malocclusion. 4, chronic diseases In the process of rapid growth and development of children some acute and chronic diseases, such as rickets, chronic rhinitis and palatine tonsils, etc., will be to prevent the normal development of the jaws, thus causing malocclusion. 5, the teething period bad habits children grow to 6-13 years old into the teething period, there will be some bad habits “finger sucking habit”, “lip biting habit”, “play tongue habit “, “biting habits”, are common factors that cause malocclusion during this important period of tooth replacement. 6, retained milk teeth As it is the root of milk teeth is not absorbed or not completely absorbed, and even some milk teeth root and alveolar bone stick together, resulting in the milk teeth still rely on not falling off when it comes to fall off. The replacement permanent teeth have no position, so they have to find a part with less resistance to erupt, resulting in “double teeth” or failing to erupt buried in the jawbone. At this time, we should find a doctor to remove the retained milk teeth in time, so that the permanent teeth just erupted can adjust themselves and gradually move to the normal position. 7.Dental caries is the most common disease in children’s mouth and one of the main causes of malocclusion of permanent teeth. Therefore, it is necessary to actively treat the caries of both baby teeth and permanent teeth. In addition, early loss of baby teeth, insufficient wear of baby cuspids, sinking teeth, congenital missing teeth, multiple teeth, transposition teeth and other common eruption abnormalities during the period of teeth replacement can lead to the occurrence of malocclusion. This requires awareness from our parents and teachers and vigilance from our community doctors. We need to pay attention to every detail to prevent risk factors in the bud. In conclusion, there are many causes of malocclusion, and not only one factor can cause malocclusion, but also several factors that work together to make malocclusion more complex. However, if we parents can understand the causes of malocclusion and fully understand the abnormalities and bad habits of children in the process of growth and development. Combined with the professional advice of orthodontists. We can really achieve early detection, early prevention, early correction, early treatment, to protect the beauty and health of the child’s face.