The irregularity of the milk teeth does not usually affect the permanent teeth, because the irregularity is sometimes affected by hereditary factors, underdevelopment of the jawbone, or early loss of the milk teeth, resulting in irregular permanent teeth. In this case, children should be allowed to eat more hard foods such as nuts and fibers to promote bone development. In addition, because the bone can stimulate growth and development through chewing, only when there is enough space can the permanent teeth have a place to erupt and the teeth can be straight. Insufficient bone development will affect the gap for teeth to grow out, resulting in misalignment of teeth. Therefore, if the baby teeth are not aligned, it does not mean that the permanent teeth are not aligned. At this time, the bone development can be stimulated to provide more space for the teeth.