Active dentures are divided into two categories: removable partial dentures and full dentures. Removable partial dentures are further divided into: traditional snap ring-type removable partial dentures, precision attachment removable partial dentures (that is, the use of various high-precision buttons or locks and other accessories to fix the removable partial dentures and perform chewing Prosthesis. Beautiful and stable than snap ring type removable partial denture, sleeve crown removable partial denture (use the original abutment to make sleeve crown. More beautiful and easy to clean dentures). It should be noted that due to the limitations of the material of the movable denture and the particularity of the oral environment, there is a foreign body sensation when the movable denture is first worn, which requires a period of adaptation, and the chewing function of the movable denture is not suitable for chewing.