This study aimed to evaluate the biomechanical performance of patient-specific versus conventional fixation for Le Fort I osteotomy using subject-specific finite element models derived from real surgical plans. Two distinct clinical scenarios-a minor advancement without impaction and a moderate advancement with posterior impaction-were analyzed to determine how surgical movements influence implant stress, bone stress, and maxillary micromotion. By combining surgical planning with validated computational modeling, this work provides clinically relevant insight to optimize PSI design and guide fixation strategy selection in orthognathic surgery.

Inclusion Criteria:

• Patient operated on By Pr SAVOLDELLI.
• Patient undergoing patient-specific orthognathic surgery.
• Access to numerical (digital) planning.

Exclusion Criteria:

• Previous maxillo-facial trauma.
• Facial cleft.

2 patients : one with type II maloclusion, one with type III maloclusion who previously undergone orthognathic surgery