Abstract: Abstract: With the development of modern oral implantology, more and more edentulous patients seek for implant-supported fixed restoration. In the edentulous mandible, to select the segmented restoration design or the one-piece restoration design is a problem that clinicians are very concerned about. This article discusses the related content of segmented restoration design from four aspects: physiology, mechanism, process and maintenance. It is concluded that in the edentulous mandible the segmented design is more reasonable. Only when the anatomical conditions are limited and the segmented design cannot be satisfied, the one-piece design is considered to be applied.