Invisalign is a type of removable denture, which is known for its elastic resin retainer, located at the gingival margin of natural teeth, and its good simulation. Elastomeric resin is a new type of prosthetic material, which was introduced to China from the United States in 1995. Its characteristics are high strength, suitable elasticity, good flexibility and translucency, its color is close to the natural gum tissue, with good bionic effect and very good concealment. The invisible denture is “theoretically” suitable for all kinds of missing teeth, even if the front and back teeth are missing at intervals, the remaining teeth have a large recess, and there is no common seating channel, the invisible denture is still available, because the invisible denture base has high elasticity and can be twisted, the denture can be put in place by twisting and rotating, and after seating, not only good retention, but also good closure The denture is not only well fixed in place, but also well closed and will not embed food. When the traditional invisible denture is used for posterior restoration, the normal chewing pressure will accelerate the resorption of the alveolar ridge in the missing tooth area due to the mucosal support type, so it must be designed as a transitional restoration or semi-permanent restoration.