To improve a patient-specific plate for use in orthognathic surgery.SOLUTION: An implant is configured to fix at least one first mandibular bone part relative to a second mandibular bone part that is separated from the first mandibular bone part by a bone gap. The implant comprises: a plate member including a pre-operatively bent body having a shape corresponding to a post-operative shape of a mandible when aligned with the mandible； and at least one guide including a guide body. The at least one guide abuts on each of a second front surface, top surface and bottom surface, and has a guide fixation aperture aligned with a plate fixation aperture, and the center aperture axis does not intersect the at least one guide. The at least one guide is pre-operatively bonded to the plate member so as to be configured to align the plate member with the mandible when the implant is positioned with respect to the mandible after the mandible has been separated so as to define the bone.SELECTED DRAWING: Figure 7A
