Deep overjet can be aggravated with age if not corrected in time for growing children, while it can be relatively stable for late-growing children and adults. Deep overjet is mainly caused by abnormal development of the upper and lower dental arches or the vertical direction of the jaw. It is characterized by excessive coverage of the mandibular anterior teeth by the maxillary anterior teeth, deep chin-lip sulcus, and short face shape. In the growth period of children, since the growth and development of the jaws is not yet completed, if not corrected as early as possible, the jaws, alveolar bone and teeth will lose the vertical constraints in their growth and development, resulting in overgrowth in the vertical direction, which will aggravate the degree of deep overjet. In the late stage of growth and adulthood, the growth and development of the jawbone is basically completed, and the teeth and alveolar bone are in a relatively stable state, and at this time, the state of deep overjet is also relatively stable. However, for some people who have the habit of grinding their teeth at night, the deep overjet can be aggravated when the back teeth are overly worn out, resulting in a lowering of the intermaxillary distance. When the symptoms of deep overjet appear, it is recommended to consult the orthodontist as soon as possible to find out the cause of the disease and early correction, which is conducive to the maintenance of orthodontic effect in the later stage.