title: Optimizing Hybrid Occlusion in Face-Jaw-Teeth Transplantation: A Preliminary Assessment of Real-Time Cephalometry as Part of the Computer-Assisted Planning and Execution Workstation for Craniomaxillofacial Surgery.
abstract: BACKGROUND
  The aesthetic and functional outcomes surrounding Le Fort-based, face-jaw-teeth transplantation have been suboptimal, often leading to posttransplant class II/III skeletal profiles, palatal defects, and "hybrid malocclusion." Therefore, a novel technology-real-time cephalometry-was developed to provide the surgical team instantaneous, intraoperative knowledge of three-dimensional dentoskeletal parameters.
  
  
  METHODS
  Mock face-jaw-teeth transplantation operations were performed on plastic and cadaveric human donor/recipient pairs (n = 2). Preoperatively, cephalometric landmarks were identified on donor/recipient skeletons using segmented computed tomographic scans. The computer-assisted planning and execution workstation tracked the position of the donor face-jaw-teeth segment in real time during the placement/inset onto recipient, reporting pertinent hybrid cephalometric parameters from any movement of donor tissue. The intraoperative data measured through real-time cephalometry were compared to posttransplant measurements for accuracy assessment. In addition, posttransplant cephalometric relationships were compared to planned outcomes to determine face-jaw-teeth transplantation success.
  
  
  RESULTS
  Compared with postoperative data, the real-time cephalometry-calculated intraoperative measurement errors were 1.37 ± 1.11 mm and 0.45 ± 0.28 degrees for the plastic skull and 2.99 ± 2.24 mm and 2.63 ± 1.33 degrees for the human cadaver experiments. These results were comparable to the posttransplant relations to planned outcome (human cadaver experiment, 1.39 ± 1.81 mm and 2.18 ± 1.88 degrees; plastic skull experiment, 1.06 ± 0.63 mm and 0.53 ± 0.39 degrees).
  
  
  CONCLUSIONS
  Based on this preliminary testing, real-time cephalometry may be a valuable adjunct for adjusting and measuring "hybrid occlusion" in face-jaw-teeth transplantation and other orthognathic surgical procedures.
authors.affiliation: Laurel, Baltimore, and Bethesda, Md.; and Boston, Mass. From the Johns Hopkins University Applied Physics Laboratory; the Department of Mechanical Engineering, Johns Hopkins University; the Department of Plastic and Reconstructive Surgery, Johns Hopkins University School of Medicine; Craniofacial Imaging, Naval Postgraduate Dental School, 3D Medical Center, and the Department of Ear, Nose, and Throat-Head and Neck Surgery, Walter Reed National Medical Center; and Harvard School of Dental Medicine/Harvard Medical School.
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Murphy
authors.forename: Ehsan
authors.initials: E
authors.lastname: Basafa
authors.forename: Sepehr
authors.initials: S
authors.lastname: Hashemi
authors.forename: Gerald T
authors.initials: GT
authors.lastname: Grant
authors.forename: Peter
authors.initials: P
authors.lastname: Liacouras
authors.forename: Srinivas M
authors.initials: SM
authors.lastname: Susarla
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Otake
authors.forename: Gabriel
authors.initials: G
authors.lastname: Santiago
authors.forename: Mehran
authors.initials: M
authors.lastname: Armand
authors.forename: Chad R
authors.initials: CR
authors.lastname: Gordon
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D059925:Anatomic Landmarks; D002102:Cadaver; D002508:Cephalometry / Q000379:methods*; D019465:Craniofacial Abnormalities / Q000175:diagnosis / Q000601:surgery*; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D005145:Face / Q000002:abnormalities / Q000601:surgery; D054445:Facial Transplantation / Q000379:methods*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D007569:Jaw Abnormalities / Q000601:surgery; D019647:Oral Surgical Procedures / Q000379:methods; D056948:Orthognathic Surgical Procedures / Q000379:methods; D012680:Sensitivity and Specificity; D025321:Surgery, Computer-Assisted / Q000379:methods*; D014071:Tooth Abnormalities / Q000601:surgery