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

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). Conclusion: 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.

[1]  S Baumrind,et al.  The reliability of head film measurements. 2. Conventional angular and linear measures. , 1971, American journal of orthodontics.

[2]  F W Pirruccello,et al.  Plastic and reconstructive surgery. , 1967, IMJ. Illinois medical journal.

[3]  Norman Wahl,et al.  Orthodontics in 3 millennia. Chapter 7: Facial analysis before the advent of the cephalometer. , 2006, American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics.

[4]  F. Costantinides,et al.  Overjet and Overbite Influence on Cyclic Masticatory Movements: A CT Study , 2013, ISRN radiology.

[5]  M. Drangsholt,et al.  Overbite and overjet are not related to self-report of temporomandibular disorder symptoms. , 2002, Journal of dental research.

[6]  W J Houston,et al.  The analysis of errors in orthodontic measurements. , 1983, American journal of orthodontics.

[7]  A. Glaros,et al.  Impact of overbite on indicators of temporomandibular joint dysfunction. , 1992, Cranio : the journal of craniomandibular practice.

[8]  M W Vannier,et al.  Craniofacial measurements based on 3D-CT volume rendering: implications for clinical applications. , 2004, Dento maxillo facial radiology.

[9]  Mehran Armand,et al.  Establishing Cephalometric Landmarks for the Translational Study of Le Fort–Based Facial Transplantation in Swine: Enhanced Applications Using Computer-Assisted Surgery and Custom Cutting Guides , 2014, Plastic and reconstructive surgery.

[10]  É. Arnaud,et al.  Midface surgery from Tessier to distraction , 1999, Child's Nervous System.

[11]  P. Cordeiro,et al.  Microvascular Reconstruction of Oncologic Defects of the Midface , 2010, Plastic and reconstructive surgery.

[12]  J. Salzmann.  The face in profile; an anthropological X-ray investigation on Swedish children and conscripts , 1948 .

[13]  C. Gordon,et al.  Craniomaxillofacial Reconstruction Using Allotransplantation and Tissue Engineering: Challenges, Opportunities, and Potential Synergy , 2011, Annals of plastic surgery.

[14]  Leonard B Kaban,et al.  Osteocutaneous Maxillofacial Allotransplantation: Lessons Learned from a Novel Cadaver Study Applying Orthognathic Principles and Practice , 2011, Plastic and reconstructive surgery.

[15]  Y J Chen,et al.  Comparison of landmark identification in traditional versus computer-aided digital cephalometry. , 2009, The Angle orthodontist.

[16]  Ryan J. Murphy,et al.  Preliminary Development of a Workstation for Craniomaxillofacial Surgical Procedures: Introducing a Computer-Assisted Planning and Execution System , 2014, The Journal of craniofacial surgery.

[17]  Ryan J. Murphy,et al.  Modeling the biomechanics of swine mastication--an inverse dynamics approach. , 2014, Journal of biomechanics.

[18]  Birdsall Holly Sr Broadbent,et al.  Bolton standards of dentofacial developmental growth , 1975 .

[19]  E. Fishman,et al.  Overcoming Cross-Gender Differences and Challenges in Le Fort–Based, Craniomaxillofacial Transplantation With Enhanced Computer-Assisted Technology , 2013, Annals of plastic surgery.

[20]  Daniel S. Alam,et al.  The technical and anatomical aspects of the World's first near-total human face and maxilla transplant. , 2009, Archives of facial plastic surgery.

[21]  C. Steiner.  Cephalometrics for you and me , 1953 .

[22]  B Trpkova,et al.  Cephalometric Landmarks Identification and Reproducibility: a Meta Analysis Materials and Methods Selection of Studies and Landmarks , 2022 .

[23]  S. Bishara.  Textbook of orthodontics , 2014 .

[24]  Ryan J. Murphy,et al.  Computer-assisted, Le Fort-based, face–jaw–teeth transplantation: a pilot study on system feasiblity and translational assessment , 2015, International Journal of Computer Assisted Radiology and Surgery.

[25]  T. Gómez-Cía,et al.  Facial transplantation: A concise update , 2012, Medicina oral, patologia oral y cirugia bucal.

[26]  S. Harrison,et al.  Operative correction by osteotomy of recessed malar maxillary compound in a case of oxycephaly. , 1950, British journal of plastic surgery.

[27]  F.A.C.S. Michael J. Yaremchuk M.D..  Making Concave Faces Convex , 2004, Aesthetic Plastic Surgery.

[28]  S Baumrind,et al.  The reliability of head film measurements. 1. Landmark identification. , 1971, American journal of orthodontics.

[29]  P. Tessier.  THE DEFINITIVE PLASTIC SURGICAL TREATMENT OF THE SEVERE FACIAL DEFORMITIES OF CRANIOFACIAL DYSOSTOSIS: Crouzon's and Apert's Diseases , 1971, Plastic and reconstructive surgery.

[30]  F. Peter.  [The classification of malocclusion]. , 1949, Osterreichische Zeitschrift fur Stomatologie.

[31]  J. Mulliken,et al.  Prelaminated free flap reconstruction of complex central facial defects. , 1999, Plastic and reconstructive surgery.

[32]  N Ohhata,et al.  Three-dimensional analysis of craniofacial bones using three-dimensional computer tomography. , 1992, Journal of cranio-maxillo-facial surgery : official publication of the European Association for Cranio-Maxillo-Facial Surgery.

[33]  T. Turvey,et al.  The hierarchy of stability and predictability in orthognathic surgery with rigid fixation: an update and extension , 2007, Head & face medicine.

[34]  B. Holly Broadbent,et al.  A NEW X-RAY TECHNIQUE and ITS APPLICATION TO ORTHODONTIA , 2009 .