title: Rapid prototyping in craniofacial surgery: using a positioning guide after zygomatic osteotomy - A case report.
abstract: BACKGROUND
  The management of post-traumatic deformity in the midface region poses challenges for the maxillofacial surgeon. Ensuring symmetry after zygomatic osteotomy can be difficult and precise positioning of the osteotomised bony fragments requires careful treatment planning. It may be necessary to use a coronal flap to allow the surgeon to compare the contralateral zygomatic bone to allow symmetrical reduction. The authors present a new technique for the positioning of osteotomised zygomatic bones using a combination of computer assisted surgical simulation and rapid prototyping.
  
  
  METHODS
  A patient presented to our unit with a post-traumatic zygomatic deformity. Using surgical simulation software the displaced zygomatic bone was osteotomised and placed in the idéal position on a three-dimensional computed tomography scan (3D CT). The position was determined by reference to the contralateral zygoma. In addition the repositioning of the soft tissues was simulated. A surgical guide which allowed intraoperative positioning of the osteotomised zygoma was manufactured by a rapid prototyping process. Use of the guide allowed a minimally invasive approach to the affected zygoma. The post-operative results were compared to the predicted outcome.
  
  
  RESULTS
  The post-operative appearance was satisfactory and corresponded well with the predicted result. There was a significant reduction in operative time compared to the previous management of similar cases.
authors.affiliation: Oral and Maxillo-Facial Surgery (Head: Jean-Luc Béziat), Hôpital de la Croix-Rousse, 103 Grand-Rue de la Croix-Rousse, 69317 Lyon, France; Plastic and Cranio-Facial Unit, Hôpital Lapeyronie, 371 avenue du doyen Gaston Giraud, 34295 Montpellier, France.
authors.forename: Christian
authors.initials: C
authors.lastname: Herlin
authors.forename: Matthieu
authors.initials: M
authors.lastname: Koppe
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Béziat
authors.forename: Arnaud
authors.initials: A
authors.lastname: Gleizal
mesh_terms: D003198:Computer Simulation; D017076:Computer-Aided Design; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008875:Middle Aged; D008953:Models, Anatomic; D010027:Osteotomy; D010347:Patient Care Planning; D011300:Preoperative Care; D019651:Plastic Surgery Procedures / Q000379:methods*; D025321:Surgery, Computer-Assisted; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014584:User-Computer Interface; D015050:Zygoma / Q000000981:diagnostic imaging / Q000601:surgery*; D015051:Zygomatic Fractures / Q000601:surgery*