Normally, new teeth come in about 1-3 months after a child loses a tooth, and a person normally has two sets of teeth, milk teeth and permanent teeth. The baby teeth start to erupt at the age of half a year, and basically erupt by the age of two and a half. At the age of six, the permanent teeth begin to erupt and alternate with the baby teeth. Normally, as the permanent teeth develop and progress, the roots of the baby teeth will resorb and cause the baby teeth to loosen, and when the permanent teeth are about to erupt, the roots of the baby teeth will be completely resorbed and will fall out of the mouth. If there is enough space for the permanent teeth to erupt and the gums are weak and unobstructed, the permanent teeth can erupt normally, usually about 1-3 months after tooth loss. If the permanent teeth have not erupted after 3 months, it is recommended to visit a dentist and have dental imaging.