Precision attachments refer to partial removable dentures, movable-fixed combined dentures, and fixed bridges provided by precision attachments. The precision attachment is an interlocking fixing device, one part is fixed on the abutment, and the other part is connected with the base of the denture to play the role of retention and support stability. In line with biological principles, it can buffer jaw force, reduce torque, protect abutment teeth, have flexible design and beautiful restoration.