first, we need to understand a tooth at the position in the tooth bow from the result of various strength interaction, once losing balance, will result in the variety of tooth position.The Lin tooth moves toward the missing tooth cleft inclination, will ascend to the Han tooth long or next hang, result in to bite(the tooth word add to match) mess.If the baby tooth leads to be pull out early or sheds off, will result in the Heng tooth harbour difficulty, the wrong harbour an etc.[ and cause to bite(the tooth word add to match) mess.Therefore, it is clinical to up often adopt currently a kind of is called cleft to keep a machine of equip, keep the position cleft of imperfection tooth, create a condition to bite(the tooth word add to match) by prevent