Underdeveloped jaws crowded teeth more hard food can play a certain role in assisting. Teeth are divided into milk teeth, replacement teeth, permanent teeth, due to bad oral habits such as breathing through the mouth, finger sucking, etc., affecting the development of the jawbone or the narrowing of the dental arch leading to crowding of the teeth. Chewing hard food, the pressure on the teeth will be transmitted to the jawbone, and this physiological stimulation can promote the development of the jawbone. Underdeveloped jaws with crowded teeth are recommended to be corrected by orthodontics as early as possible. An orthodontist can be consulted. Through detailed examination and taking of orthostatic and lateral films of the skull, the doctor will suggest an optimal orthodontic program to the patient through measurements. Patients should develop the habit of brushing their teeth in the morning and evening and rinsing their mouths after meals. When discomfort occurs, it is recommended to go to the dental clinic in time for standardized examination to clarify the cause of the disease and then reasonably treat it.