You are in: eMedicine Specialties > Plastic Surgery > CRANIOFACIAL Craniofacial, Orthognathic SurgeryArticle Last Updated: Sep 5, 2006AUTHOR AND EDITOR INFORMATIONSection 1 of 11
  Author: Pravin K Patel, MD, Associate Professor of Surgery, Division of Plastic Surgery, Northwestern University School of Medicine, Chief of Plastic & Craniofacial Surgery, Shriners Hospitals for Children, Head of Craniofacial Surgery, Children's Memorial Hospital Coauthor(s): Andrew Gassman, MD Editors: John Persing, MD, Chief, Professor, Department of Surgery, Sections of Plastic Surgery and Neurosurgery, Yale University School of Medicine; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; R Edward Newsome, MD, Associate Professor, Program Director and Chief, Department of Surgery, Section of Plastic Surgery, Tulane University Health Sciences Center; Nicolas (Nick) G Slenkovich, MD, Practice Director, Colorado Plastic Surgery Center at Swedish Medical Center; Susan E Downey, MD, Clinical Associate Professor, Department of Surgery, Division of Plastic Surgery, University of Southern California Author and Editor Disclosure Synonyms and related keywords: jaw surgery, dentofacial skeletal surgery, facial orthopedic surgery, craniofacial surgery, orthognathic surgery INTRODUCTIONSection 2 of 11
  Orthognathic surgery involves the surgical manipulation of the elements of the facial skeleton to restore the proper anatomic and functional relationship in patients with dentofacial skeletal anomalies. This article provides an overview of the principles used in orthognathic surgery, which can be used to manage a broad spectrum of maxillofacial abnormalities, including congenital, developmental, and acquired deformities. History of the ProcedureWhile an exhaustive history is not possible, a brief chronologic history of orthognathic procedures follows. Mandibular osteotomies 1846 - Hullihan - Anterior mandibular subapical osteotomy and setback 1906 - Blair - Mandibular body osteotomy 1907 - Blair - Horizontal osteotomy of the ramus, external approach 1925 - Limberg - Posterior oblique vertical ramal osteotomy, external approach 1927 - Wassmund - Inverted "L" ramal osteotomy, external approach 1939 - Kazanjian - Beveled horizontal osteotomy of the ramus, extraoral approach 1942 - Schuchardt - Step horizontal osteotomy of the ramus, intraoral approach 1954 - Caldwell and Letterman - Vertical ramal osteotomy, external approach 1955 - Obwegeser - Sagittal split ramal osteotomy 1968 - Caldwell et al - "C" ramal osteotomy 1970 - Hebert, Kent, and Hinds - Intraoral vertical ramal osteotomy Maxillary osteotomies 1927 - Wassmund - LeFort I osteotomy with the pterygomaxillary junction left intact; elastic forces used to bring the maxilla forward 1928 - Axhuasen - Segmental osteotomy through the mid palate 1942 - Schuchard - Staged LeFort I osteotomy, followed by pterygomaxillary separation; external traction used to bring the maxilla forward 1949 - Moore and Ward - Horizontal transection of the pterygoid plate 1965 - Obwegeser - Fully mobilized the maxilla; in a single step brought it into the predicted position Osseous genioplasty procedures 1942 - Hofer - Horizontal sliding osteotomy of a receding chin (extraoral) 1957 - Trauner and Obwegeser - Intraoral approach to osseous genioplasty Historically, the ability to reposition the mandible in a stable manner long preceded the ability to reposition the maxilla. As a consequence, many patients underwent only mandibular surgery to correct a primary maxillary deformity. The specialty of orthognathic surgery did not fully develop until Obwegeser demonstrated the possibility of repositioning the maxilla in a stable consistent manner in 1965 and reported simultaneous repositioning of the maxilla and mandible in 1970. ProblemThe word orthognathic comes from the Greek word orqos, meaning to straighten, and gnaqos, meaning jaw. Orthognathic surgery thus means to straighten a jaw. Defining a straight jaw versus one that is not requires determining the degree of deviation from a specified population norm. Nevertheless, restoring the orthognathic form of the face ultimately depends upon achieving the ideal facial esthetics of the individual patient, not simply restoring the average normative values of a population. Remember that the face is more than the upper and lower jaw; when deformities extend to involve the cranio-orbital skeleton, evaluation and management expand the scope of maxillofacial surgery to craniofacial surgery. Thus, orthognathic or maxillofacial surgery is a subset of craniofacial surgery. Correction of maxillofacial deformities requires careful analysis of the soft tissue with clinical examination and supporting photographs, skeletal evaluation with standardized radiographs, and dental evaluation with study dental casts. Formulation of a treatment plan thus requires close cooperation of the surgeon working with the dentist, the orthodontist, and at times the restorative prosthodontist. Unlike many surgical procedures, outcome depends not only on the surgical procedure but also on a multitude of factors that begin long before the actual surgery as well as on control of the variables long after surgery. FrequencyThe exact incidence of dentofacial deformities requiring orthognathic surgery is difficult to estimate because it includes a broad population of patients with deformities of congenital, developmental, and traumatic origin. However, the number of individuals with developmental dentofacial deformities in the United States who may benefit from orthognathic surgery is estimated at 1.5-2 million; of these, approximately 1 million present with Class II deformities and 0.5 million with Class III deformities. EtiologyDentofacial skeletal anomalies generally occur as a result of a differential in growth of the upper facial skeleton to the lower facial skeleton, resulting in discrepancy of the normal relationship that exists between the upper and lower jaw. Underlying genetic predisposition and acquired causes can influence the normal growth of the facial skeleton. Congenital anomalies, from syndromic conditions such as Apert and Crouzon syndromes to facial clefts, affect normal growth and development. Traumatic events in the mature skeleton can displace the normal elements and require repositioning osteotomies if improperly reduced initially. Traumatic events in the developing facial skeleton can disturb normal subsequent growth. Other etiologies that can result in significant dentofacial anomalies include neoplastic growth, surgical resection, and iatrogenic radiation. However, of all the etiologies, developmental anomalies representing the extremes of population norms are the most common conditions requiring orthognathic surgery. ClinicalA wide range of clinical presentations is possible, some of which are outlined in Table 1 below. Diagnosis is based on a comprehensive assessment that includes clinical examination, skeletal evaluation with standardized radiographs, and dental evaluation with study dental casts addressed as an integral part of the workup (see Image 3). Clinical assessment should be directed specifically at evaluating the relative position and size of each of the facial skeletal elements, the degree of zygomatic projection, and the maxillary and mandibular positions in space relative to each other and to the cranial-orbital region. The nasolabial angle, upper lip length, lip competency, labial-mental sulcus, and cervicomental angle should be documented. Any facial asymmetry should be noted along with the relationship of the maxillary dental mid line to the mandibular dental mid line and the dental mid lines to the facial mid line. The intraoral examination should focus on the dental alignment within each arch and relationship of the dental arches to each other. The degree of dental display on repose and smile also should be recorded with the amount of gingival display. Facial balance typically is assessed by dividing the face in thirds. The upper third is from the anterior hairline (trichion) to the glabella, the middle third from the glabella to the subnasale, and the lower third from the subnasale to the menton. When each of the thirds is equal, the face is said to be balanced and of "ideal" proportions. Additionally, in profile view the face should have a slight degree of convexity as measured from the glabella to the subnasale to the menton. Excess facial convexity, flatness, or concavity is felt to be less than ideal (see Image 2). However, facial proportions are only idealized concepts and have changed over time. They merely provide a guideline that is not true for every patient; a wide range of aesthetic faces defies such absolute cannons (see Image 1). Maxillofacial deformities can be divided broadly into 3 major categories: (1) dental dysplasias, (2) skeletal dysplasias, and (3) dentoskeletal dysplasias. Dental dysplasias Dental dysplasias are limited strictly to malocclusions that result from abnormal spatial relationship of the dentition and not from the skeletal position of the upper and lower jaws. These can be corrected with orthodontic treatment. Skeletal dysplasias In patients with skeletal dysplasia only, the dentition is in good alignment, but the maxilla and/or mandible are dysplastic. Skeletal dysplasias require correcting the skeletal deformity without altering the occlusion. An example is a patient with retrogenia without retrognathia or a patient with hemifacial microsomia who has a normal maxillary-mandibular dental relationship but has an occlusal cant because of skeletal asymmetry. Dentoskeletal dysplasias In dentoskeletal dysplasias, the dentition is malpositioned within each arch and with each other; additionally, the skeletal relationship of the upper and lower jaws is abnormal. An example is a patient with a maxillary sagittal and transverse width deficiency from a facial cleft. Correction requires aligning the dentition within each arch with orthodontic treatment and restoring the maxillary-mandibular dental relationship with skeletal osteotomies and repositioning. In addition, dentoskeletal dysplasias can be classified further based on the position in space and on the volume or mass (whether deficient or in excess) of the individual elements. For example, the mandible can be of normal shape and volume but retrognathic in relationship to the maxilla, or it may be both retrognathic and volumetrically deficient. Table 1. Typical Presentation of Maxillofacial Deformities
* SNA=Sella-nasion-A point angle † SNB=Sella-nasion-B point angle ‡ ANB=A point-nasion-B point angle § FH=Frankfort horizontal ¶ Ar-Gn=Articulare-gnathion INDICATIONSSection 3 of 11
Indications for orthognathic surgery include facial dysmorphism with and without functional implications. As an illustration, an osseous genioplasty for a patient with retrogenia but without malocclusion should be considered for facial form. If the retrogenia is associated with retrognathism resulting in a malocclusion, orthognathic surgery is indicated for restoring the facial form and for functional occlusion. Airway and speech are other indications when considering the functional need for orthognathic surgery. Restoration of the normal anatomic relationship between the maxilla and mandible relative to the cranial base reestablishes the functional components (ie, form and function) of the facial skeleton. RELEVANT ANATOMYSection 4 of 11
As relevant skeletal and neurovascular anatomy can be found in many anatomic atlases, this section focuses on specific aspects pertinent to the procedures described. With maxillary osteotomies, an understanding of the vascular blood supply to the mobilized maxilla is crucial. The arterial blood supply to the maxilla is derived from 4 primary sources: (1) the descending palatine branch of the maxillary artery, (2) the ascending palatine branch of the facial artery, (3) the anterior branch of the ascending pharyngeal artery from the external carotid, and (4) the alveolar branches of the maxillary artery. With complete mobilization of the maxilla, frequently the descending palatine vessels are disrupted and the mobilized maxilla derives its vascularity from the remaining sources, primarily the ascending palatine and pharyngeal vessels. To avoid neurosensory deficits with mandibular osteotomies, the surgeon must be cognizant of the course of the inferior alveolar nerve from its entrance at the mandibular foramen on the medial aspect of the ramus to its emergence from the mental foramen between the first and second premolars. Vertically, the mandibular foramen typically lies approximately 8 mm inferior to the lingula mandibularis (the anterior wall of the mandibular foramen), and the lingula is approximately 5 mm above the occlusal plane. With the sigmoid notch as a reference point, the foramen is approximately 20 mm inferior. Regarding the anterior-to-posterior relationship, the foramen is located 20 mm from the anterior mandibular ramal border, a depth of approximately two thirds of the total mandibular ramal width. The canal then courses within the mandible, measuring 2-2.5 mm in diameter. Its lowest point from the inferior mandibular border is in the region of the first and second molars, approximately 7.5 mm, before continuing anterior and superior to its emergence from the mental foramen, where it is approximately 8 mm from the inferior border. At the mental foramen, the canal extends caudally before emerging. Regarding the transverse position of the canal within the mandible, it is most superficial in the region of the third molar, approximately 2 mm from the buccal plate. In the region of the first molar, it is 4 mm from the buccal plate. Dental ConceptsA number of basic dental concepts pertinent to orthognathic surgical procedures are important. Dental notation Universal Dental Notation is the most common system for numerically identifying permanent dentition. The maxillary dentition is numbered sequentially from 1-16 starting with the right maxillary third molar as 1. The numbering system continues from 17-32 beginning with the left mandibular third molar as 17. Orientation terms Orientation with respect to intraoral anatomy is referenced to the following terms:
Dental anatomic terms
Occlusal classification The classification of dental occlusions is based on Edward Angle's observation in 1899 that the key to occlusion is the relationship of the mandibular first molar to the maxillary first molar.
Angle's original classification has been expanded to include the anterior dentition. Class II is subdivided further to include the angulation of the anterior dentition. In Class II, Division 1, the molar relationship is Class II, but the maxillary anterior teeth are flared labial. In Class II, Division 2, the molar relationship is Class II, but both the maxillary and mandibular anterior teeth are retruded with a deep bite. The terms Class I, II, and III also are used to relate the maxillary and mandibular canine relation. The Angle classification relates only to maxillary dentition with the mandibular dentition. While it generally is assumed that a similar skeletal relationship of Class I, II, and III follows, this is not always the situation. A Class I molar relationship is possible with a Class II skeletal relationship by dental extractions and orthodontic alignment without regard to basal skeletal morphology. Upper and lower arch dentition Additional terms are used to describe the relationship between the dentition of the upper and lower arches.
Dental compensations The anterior dentition typically inclines so as to partly offset the malocclusion and may allow some degree of anterior occlusion to occur depending on the maxillary-mandibular discrepancy. In prognathism, the lower incisors may be flared lingual and the upper incisors flared labial to compensate for the Class III malocclusion. Conversely, with mandibular deficiency the opposite occurs; the mandibular dentition is flared labial and the maxillary dentition flared lingual. Centric relation and centric occlusion Centric relation is the most retruded position of the condyle within the glenoid fossa (terminal hinge position). It refers to the condylar-glenoid fossa relation but does not indicate the occlusion. Centric occlusion indicates the maximum intercuspal contact of the dentition and does not refer to the condylar position. In the ideal situation, when the patient is in centric occlusion (maximum), the condylar-glenoid is in proper centric relation. CONTRAINDICATIONSSection 5 of 11
A number of risk factors may alter the treatment plan or preclude surgery, including underlying medical conditions, bleeding dyscrasias, systemic disease or local factors that may affect normal wound healing, compromised vascularity of the surgical region, a patient with unrealistic expectations, a noncompliant patient, and patients with poor oral hygiene. WORKUPSection 6 of 11
Imaging Studies
Other Tests
TREATMENTSection 7 of 11
Surgical TherapyThe elements of the facial skeleton can be repositioned, redefining the face through a variety of well-established osteotomies, including LeFort I-type osteotomy, LeFort II-type osteotomy, LeFort III-type osteotomy, maxillary segmental osteotomies, sagittal split osteotomy of the mandibular ramus, vertical ramal osteotomy, inverted L and C osteotomies, mandibular body segmental osteotomies, and mandibular symphysis osteotomies. Most maxillofacial deformities can be managed with 3 basic osteotomies: the mid face with the LeFort I-type osteotomy, the lower face with the sagittal split ramal osteotomy of the mandible, and the horizontal osteotomy of the symphysis of the chin. Mid face Various osteotomies are used to correct midfacial deformities, and the choice of procedure depends on the specific deformity. The LeFort osteotomies are named after the 3 classic lines of weakness of the facial skeleton described by Rene LeFort in 1901. Complete craniofacial dysjunction by the LeFort III osteotomy allows the surgeon to alter the orbital position and volume, zygomatic projection, position of the nasal root, frontonasal angle, and position of the maxilla and to lengthen the nose. The LeFort II osteotomy allows the surgeon to alter the nasomaxillary projection without altering the orbital volume and zygomatic projection. The LeFort I osteotomy allows for correction primarily at the occlusal level affecting the upper lip position, nasal tip and alar base region, and the columella labial angle without altering the orbitozygomatic region. Nevertheless, remember that these standard LeFort osteotomies frequently must be modified to address the specific clinical situation. For example, modify the standard LeFort I osteotomy to include a portion of the body of the zygoma when the lower maxillary deficiency is accompanied with inadequate zygomatic projection but the orbit does not require alteration as it does in a LeFort III. The LeFort II and III osteotomies generally are part of the treatment plan in the major craniofacial dysotosis syndromes and are described elsewhere. For most midfacial maxillofacial deformities, the LeFort I osteotomy and its variations are adequate. Lower face For the lower face, various osteotomies are used to correct mandibular deformities, and the choice depends on the particular deformity. Currently, the sagittal split ramal osteotomy is the primary choice for correcting most cases of mandibular retrognathism and prognathism. In extreme cases of mandibular prognathism, some surgeons prefer the intraoral vertical osteotomy or the inverted L osteotomy. In situations of mandibular advancement in which the mandibular rami is hypoplastic and cannot be sagittally split, the inverted L and the C osteotomy with bone grafts are preferred. Deformities of the chin can exist independently of mandibular deformities, and the chin can be abnormally proportioned without occlusal involvement. While alloplastic chin implants are used most commonly for correction of minimal sagittal chin deficiencies, the horizontal osteotomy of the symphysis (osseous genioplasty) is a far more versatile procedure. The chin can be repositioned in multiple planes, allowing for correction of significant sagittal and vertical deformities of deficiency (microgenia) or excess (macrogenia) and asymmetric conditions. Preoperative DetailsBegin treatment planning by reviewing the various orthodontic and surgical options that address the problem list. Primarily, decide whether the deformity is significant enough to require surgical repositioning or if orthodontic alignment of the dentition can be achieved without significantly compromising facial esthetics. If contemplating surgical intervention, the question arises whether to intervene prior to completion of skeletal growth or to await skeletal maturity to eliminate the variability of subsequent growth and the need for further surgical intervention. Once the decision is made for combined dental-surgical correction, carefully plan the overall treatment with input from all specialists. The management can be divided into the following 5 phases:
Preorthodontic preparatory phase Prior to the formal start of the presurgical orthodontic treatment phase, treat acute periodontal disease and caries as part of phase 1. Reduce gingival inflammation with cleaning and good oral hygiene. Treat poorly attached gingiva prior to orthodontic tooth movement. Decide whether caried dentition can be restored either temporarily or permanently and whether endodontic treatment or extraction is required. Presurgical orthodontic treatment phase Once the state of oral hygiene is maximized, the presurgical orthodontic treatment phase can begin. Initially, decide whether any dentition requires extraction. This depends on the incisor positions and the degree of dental crowding within a limited arch length. Sufficient space must be present to allow the dentition to be placed within the supporting basal bone. Instead of extractions, expansion of the arch may be the ideal choice. If the midpalatal suture is open, expansion may be accomplished orthodontically with a palatal expansion device; otherwise, this may require surgical assistance with an osteotomy. Extractions also may be required to allow for maximum skeletal repositioning to improve final facial esthetics. If a mandibular osteotomy such as a sagittal split is contemplated, extracting the mandibular third molars well in advance, typically 8-12 months prior, generally is wise to minimize the risk of an unfavorable osteotomy and to allow for rigid internal fixation. During this phase, orthodontically align the dentition within the dental arch, level the curve of Spee, and decompensate the anterior dentition (see Images 7-8). This is performed independently within each of the dental arches without any attempt at correcting the occlusion. Because of this, malocclusion frequently is worsened; inform the patient of this. However, the maxillary and mandibular dentitions are coordinated with each other as if the surgery had been accomplished with dental casts that can be manipulated freely. Obtain progress dental models throughout the orthodontic treatment, and begin planning for surgery when they can be hand coordinated with stable occlusion. If segmental osteotomies are planned, then prepare the dentition accordingly. If osteotomies are not placed through the planned extraction sites, then prepare interdental space orthodontically, with the roots widely divergent to prevent injury and the space favorably closed at the time of surgery. Use periapical and ortho–Panorex films to evaluate the space for osteotomies. Segmental dental casts then confirm the readiness for surgery. The orthodontist then typically replaces the arch wire with a heavy rectangular wire ligated to the orthodontic brackets and surgical hooks to permit intraoperative and postoperative maxillary-mandibular fixation. At the time of surgery, no active dental movement should be occurring, with the orthodontic wire passive. If segmental osteotomies are planned, likewise segment the arch wire prior to surgery. This presurgical phase typically varies from 6-18 months depending on what needs to be accomplished to maximize final surgical stability at the occlusal level. Surgical phase Begin surgical planning by clinically re-evaluating the patient. Orthodontic movement of dentition alone alters facial features in a subtle manner (eg, amount of dental display); take this into account when planning skeletal movement. Typically, obtain radiographic studies within 2-3 weeks of the planned surgical date. Obtain and analyze a presurgical cephalometric film and make prediction tracings. Then mount the models on a semiadjustable articulator to simulate the relative position of the dentition within the facial form. Based on the clinical assessment and cephalometric prediction tracings, perform a model surgery to simulate the planned operative procedures. With the dental casts in their final position, make an acrylic splint. When repositioning of both jaws is planned, fabricate an intermediate splint in addition to the final splint. These splints allow for accurate intraoperative positioning of the maxilla and mandibular dentoalveolar segments. In addition, these splints are important to ensure postoperative stability when the maxillary and mandibular arches are insufficiently coordinated for maximum interdigitation. The details of prediction tracing, model surgery, and splint fabrication are beyond the scope of this overview article. Intraoperative DetailsThe sequence of operative procedures is based on the preoperative planning and model surgery. If a single jaw is being repositioned, use a final splint to guide the occlusion of the jaw being moved relative to the remaining jaw. If both maxillary and mandibular repositioning osteotomies are planned, use an intermediate splint to guide the movement of one jaw relative to the other jaw. While typically the maxilla is repositioned first, followed by the mandible, the sequence can be reversed with the appropriate intermediate splint. Reposition the remaining jaw based on the final splint. Once the maxilla and mandible are in their final positions, assess the chin and perform an osseous genioplasty if necessary. LeFort I operative details (see Images 9-10)
Sagittal split osteotomy of the mandibular ramus (see Image 11)
Osseous genioplasty
Postoperative DetailsAirway management is of primary concern in the immediate postoperative period, and patients require close monitoring. Obtain an ortho–Panorex view in the early postoperative period to confirm that the condyles are in their appropriate position. If the condyles are displaced, return the patient to surgery and redo the osteosynthesis. Postoperative surgical practices vary depending on surgeon preferences and the stability believed to be obtained at the time of surgery. This varies from maintenance of maxillary-mandibular fixation with wire to use of only guiding dental elastics for a varying period of 4-8 weeks. Provide close follow-up care to the patient. If the occlusion changes, elastics can be applied in the appropriate vector to guide the occlusion until bony healing is complete. During this period, advance the patient from an early liquid diet to a mechanically soft diet to minimize significant occlusal forces. Postsurgical orthodontic phase The postsurgical orthodontic phase typically begins 4-8 weeks after surgery. If used, remove the surgical splint and instruct the patient in increasing the maxillary-mandibular range of motion (limited up until this point) and in gradually returning to his or her usual diet. Return the patient to the orthodontist for finishing dental alignment with the relative position of the skeletal bases in their final position. Close any remaining interdental spaces and bring the dentition into maximum intercuspal relationship. This phase typically lasts for approximately 4-6 months and formally ends with the removal of the orthodontic braces; instruct the patient to use a retainer to maintain long-term stability. Obtain photographs, radiographic studies, and dental models at debanding of the orthodontic braces and at 1 year postoperatively. Prosthodontic treatment phase The final phase includes placement of dental implants, prosthetic and periodontal treatment, and dental restoration to improve the final dental esthetics. COMPLICATIONSSection 8 of 11
While complications can occur during any of the dental, orthodontic, or surgical phases of treatment, complications specifically related to the surgical procedures are summarized as follows: LeFort
Bilateral sagittal split osteotomy
Osseous genioplasty
Common to all procedures
OUTCOME AND PROGNOSISSection 9 of 11
Outcome depends on the surgical procedure, on a multitude of factors that begin long before the actual surgery, and on control of the variables long after the surgical procedure. Whether the desired long-term outcome is achieved in terms of occlusal function and esthetics of the facial form depends on whether the goals of each of the treatment phases were achieved. Moreover, the success of each phase depends on the preceding phase of treatment. For example, inadequate incisor decompensation limits the amount of sagittal repositioning possible and compromises final facial esthetics. If mobilization of the maxilla at the time of surgery is inadequate, obtaining a less-than-ideal occlusal relation, the postsurgical orthodontic phase is prolonged and the likelihood of relapse increased. With any skeletal movement, the surgeon always must be aware of the potential for relapse even in the most ideal situation and with the use of rigid internal fixation. Soft-tissue forces directed against the vector of the surgical movement are significant. Generally, the most stable moves are superior and posterior maxillary impactions and mandibular setback. Advancements of the maxilla, whether vertically or sagittally, are inherently less stable, as is mandibular advancement. Although orthognathic surgery involves restoring the skeletal anatomy, the patient ultimately is concerned with how the soft tissue drapes the new facial skeleton. The surgeon must be well aware of the soft-tissue response to skeletal movements. The goal is not necessarily to normalize cephalometric values; rather, the aim should be for the patient to have normal appearance and function. MULTIMEDIASection 10 of 11
REFERENCESSection 11 of 11
Craniofacial, Orthognathic Surgery excerpt Article Last Updated: Sep 5, 2006 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
