BlueCross and BlueShield of Montana Medical Policy/Codes
Orthognathic Surgery
Chapter: Surgery: Procedures
Current Effective Date: July 18, 2013
Original Effective Date: July 18, 2013
Publish Date: April 18, 2013
Revised Dates: This policy is no longer scheduled for routine literature review and update.

The word orthognathics originated from the Greek words for “straight” and “jaw”.  Orthognathic surgery is the surgical correction of abnormalities of the mandible (lower jaw), maxilla (upper jaw), or both.  The underlying abnormality may be present at birth, may become evident as an individual grows and develops, or may be the result of traumatic injuries.  Orthognathic surgery is performed to correct malocclusion or deformity that is related to functional impairment, and that cannot be improved with routine dental or orthodontic therapy. 

Maxillofacial deformities can be divided broadly into three major categories: dental dysplasias, skeletal dysplasias, and dentoskeletal dysplasias.  Dental dysplasias are 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.  In patients with skeletal dysplasia, 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.  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; correction requires aligning the dentition within each arch with orthodontic treatment and restoring the maxillary-mandibular dental relationship with skeletal osteotomies and repositioning.

Skeletal/facial anomalies are referenced as spatial (refers to space) planes: horizontal, vertical, transverse, or a combination.  Examples of conditions for which orthognathic surgery is used are mandibular prognathism, crossbite, open bite, overbite, underbite, mandibular deformity, and maxillary deformity.  Orthognathic procedures include osteotomy, ostectomy, or osteoplasty, and the insertion of material to hold bones together such as plates, screws, and wires.  Depending on the severity of the deformity, several surgical methods may be used.  In addition, orthognathic surgery is usually preceded by orthodontic therapy to attempt to correct malocclusion by conservative therapy or in preparation for surgery; orthodontic therapy may also be required in the post-operative phase.


NOTE:  Coverage for orthognathic surgery may be dependent on benefit plan language (i.e., may be subject to the provisions of a cosmetic or reconstructive surgery benefit), and/or may be subject to legislative mandates.  Please refer to the benefit plan language and/or legislative mandates to determine terms, limitations, and conditions of coverage.

Maxillary and/or Mandibular Facial Deformities Associated with Masticatory Malocclusion

When not specifically excluded from coverage in a health benefit contract, Blue Cross and Blue Shield of Montana (BCBSMT) may consider orthognathic surgery medically necessary when the following criteria are met:

1.)  Surgery is proposed for the correction of skeletal deformities when it is documented that:

  • these facial skeletal deformities are contributing to significant functional impairment,  defined as persistent difficulties with mastication and swallowing as manifested by inability to incise and/or chew solid foods, choking on incompletely masticated solid foods, damage to soft tissue during mastication; malnutrition; significant weight loss; failure-to-thrive, AND
  • deformity and impairment are not correctable with non-surgical modalities (e.g., dental therapeutics, orthodontics) AND

2.)  Skeletal deformity falls under one of the following categories:

  • Anteroposterior discrepancies (NOTE: These values represent two or more standard deviations from published norms):
    • Maxillary/Mandibular incisor relationship: overjet of 5 mm or more, or a 0 to a negative value (norm = 2 mm); or
    • Maxillary/Mandibular anteroposterior molar relationship discrepancy of 4 mm or more (norm = 0 to1 mm); OR
  • Vertical discrepancies
    • Presence of a vertical facial skeletal deformity which is two or more standard deviations from published norms for accepted skeletal landmarks; or
    • Open bite with no vertical overlap of anterior teeth or unilateral or bilateral posterior open bite greater than 2 mm; or
    • Deep overbite with impingement of palatal soft tissue; or
    • Supraeruption of a dentoalveolar segment resulting from lack of occlusion when dentition in segment is intact; OR 
  • Transverse discrepancies
    • Presence of a transverse skeletal discrepancy which is two or more standard deviations from published norms; or
    • Total bilateral maxillary palatal cusp to mandibular fossa discrepancy of 4 mm or greater, or a unilateral discrepancy of 3 mm or greater, given normal axial inclination of the posterior teeth; OR
  • Asymmetries
    • Anteroposterior, transverse or lateral asymmetries greater than 3 mm, with concomitant occlusal asymmetry.

Speech Impairment

BCBSMT may consider orthognathic surgery medically necessary for treatment of speech dysfunction that is directly related to a facial skeletal deformity, as determined by a speech and language pathologist (e.g., sibilant distortions, velopharyngeal distortion).

BCBSMT considers orthognathic surgery not medically necessary for correction of articulation disorders and other speech impairments that are not related to facial skeletal deformity.

Aesthetic and Psychological Indications

BCBSMT considers orthognathic surgery cosmetic when performed in the absence of significant functional impairment, including but not limited to:

  • when used for altering or improving bite, or
  • when performed solely for the purpose of improving or altering appearance or self-esteem, or
  • to treat psychological or psychosocial symptoms or complaints related to the member’s appearance.

Other Indications

BCBSMT considers orthognathic surgery not medically necessary for any other indication.

Advanced Member Notice of Financial Liability for Denied Services

When the criteria for coverage is not met, BCBSMT encourages all participating providers to have a member complete and sign an Advanced Member Notification (AMN) form stating that BCBSMT will not cover this service, supply, device, or drug. If an AMN is signed prior to delivery of the service, participating providers can balance bill the patient. If an AMN is not signed, participating providers are financially liable and cannot balance bill the BCBSMT member for denied services. Services provided by an out-of-state provider that are denied as not medically necessary are the financial responsibility of the patient even if an AMN is signed.

Refer to the Advanced Member Notification medical policy for more information. The AMN form is available at (Click on Providers and then Forms).

Rationale for Benefit Administration

This medical policy was developed through consideration of peer reviewed medical literature, FDA approval status, accepted standards of medical practice in Montana, Technology Evaluation Center evaluations, and the concept of medical necessity. BCBSMT reserves the right to make exceptions to policy that benefit the member when advances in technology or new medical information become available.

The purpose of medical policy is to guide coverage decisions and is not intended to influence treatment decisions. Providers are expected to make treatment decisions based on their medical judgment. BCBSMT recognizes the rapidly changing nature of technological development and welcomes provider feedback on all medical policies.

When using this policy to determine whether a service, supply or device will be covered, please note that member contract language will take precedence over medical policy when there is a conflict.

 General Information

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:

  • Mesial - Toward the dental mid line
  • Distal - Away from the dental mid line
  • Labial - Toward the lips
  • Buccal - Toward the cheek
  • Apex - Toward the root tip
  • Lingual - Toward the tongue
  • Incisal - Toward the biting surface (anterior dentition)
  • Occlusal - Toward the biting surface (posterior dentition)
  • Angulation - Mesiodistal tipping of the long axis of the tooth
  • Inclination - Labiolingual or buccolingual tipping of the long axis of the tooth

Dental anatomic terms

  • Cusp - Pronounced elevation on the occlusal surface
  • Groove - Depression on the occlusal surface
  • Crown - Visible portion of the tooth covered by enamel
  • Cingulum - Bulbous convexity of the cervical one third of the lingual surface of anterior dentition
  • Cervix (neck) - Junction of the crown and root
  • Root - Portion of the tooth covered by cementum within the alveolar bone
  • Curvature of the dental arches - Normal reciprocal curvature in the dental arches with the maxilla convex and the mandible concave (allows the dentition maximal contact during function)
  • Curve of Spee - Normal curvature of the dental arch in the sagittal plane
  • Curve of Wilson - Normal curvature of the dental arch in the coronal plane

Occlusal classification

  • Class I (neutro-occlusion): The mesiobuccal cusp of the maxillary first molar articulates within the mesiobuccal groove of the mandibular first molar.
  • Class II (disto-occlusion): The mandibular first molar articulates distal to the mesiobuccal cusp of the maxillary first molar, i.e., the mandibular teeth are behind the normal relationship with the maxillary teeth.  This can be due to a deficiency of the lower jaw or an excess of the upper jaw; may be referred to as a deep bite deformity.
  • Class III (mesio-occlusion): The mesiobuccal groove of the mandibular first molar is mesial to the mesiobuccal cusp of the maxillary first molar, i.e., the lower dental arch is in front of the (mesial to) the upper dental arch.  People with this type of malocclusion usually have a strong or protrusive chin commonly referred to as an underbite.

Upper and lower arch dentition

  • Overjet - Horizontal distance between the incisal edges of the maxillary incisor to the mandibular incisor
  • Overbite - Vertical distance between the incisal edge of the maxillary incisor and the mandibular incisor
  • Crossbite - Lingual-buccal malposition of the normal relationship between the upper and lower dentition (negative overjet)
  • Deep bite - Condition of excessive overbite
  • Open bite - Condition of negative overbite (teeth do not meet)

Imaging Studies

  • Ortho-Panorex x-rays provide an overview of the stage of dental development, the mandibular anatomy, and gross pathology.  Specific films such as occlusal and periapical views can be obtained to further assess the dentition, supporting bone, and interdental spaces.
  • Cephalometric x-rays are standardized skull and/or facial views that allow for comparison over time to assess growth in an individual and for comparison of that individual against standardized population norms.
  • Periapical films are obtained to determine if sufficient space exists for interdental osteotomies.
  • On occasion, hand wrist films are useful to help determine skeletal age based on the known timing of sequential closure of the epiphyseal growth plates.  However, typically facial skeletal maturity is determined by comparison of serial lateral cephalometric films obtained at 6-month intervals.
  • Three-dimensional computerized tomography is being increasingly used for surgical evaluation and planning in academic university settings.  In the future, such three-dimensional visualization of the patient's anatomic deformity is likely to replace today's conventional two-dimensional cephalometric analysis.

Surgical Therapy

The elements of the facial skeleton can be repositioned, redefining the face through a variety of well-established osteotomies, including LeFort (I, II, and III) osteotomies, 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 three basic osteotomies: the midface with the LeFort I osteotomy, the lower face with the sagittal split ramal osteotomy of the mandible, and the horizontal osteotomy of the symphysis of the chin.

The LeFort osteotomies are named after the three classic lines of weakness of the facial skeleton described by Rene LeFort in 1901.  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.  The LeFort II osteotomy allows the surgeon to alter the nasomaxillary projection without altering the orbital volume and zygomatic projection.  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.  These standard LeFort osteotomies may be modified for a specific clinical situation.  For most midfacial maxillofacial deformities, the LeFort I osteotomy and its variations are adequate.

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 are hypoplastic and cannot be sagittally split, the inverted L- and the C-osteotomy with bone grafts are preferred.

Additional Terminology

  • Alveolar or Alveolus – that portion of the upper and lower jaws that contain the teeth and form the dental arches
  • Apertognathia – a type of malocclusion characterized by the premature occlusion of posterior teeth and the absence of anterior occlusion; sometimes referred to as open bite
  • Dentition - The natural teeth, as considered collectively, in the dental arch; may be deciduous, permanent, or mixed
  • Dysplasia - Abnormal tissue development
  • Genial – pertaining to the chin
  • Genioplasty – surgical alteration of the chin; also called mentoplasty
  • Hyperplasia – an abnormal increase in cells in an organ or a tissue with consequent enlargement
  • LeFort - an operation for reconstruction of the midface in which the teeth-bearing part of the maxilla is separated from its bony attachments and repositioned
  • Mandible – lower jaw
  • Maxilla – upper jaw
  • Mentoplasty – surgical alteration of the chin; also called genioplasty
  • Masticatory – refers to masticatory muscles or chewing
  • Maxillary hyperplasia – Overgrowth of the maxilla, or upper jaw, often presenting as excess vertical height of the maxilla
  • Maxillary hypoplasia – an abnormally small or posteriorly positioned maxilla, or upper jaw, often accompanying cleft palate or other craniofacial syndromes
  • Micrognathia – an abnormally small mandible or lower jaw
  • Occlusal - In dentistry, pertaining to the contacting surfaces of opposing occlusal units (teeth or occlusion rims) or the masticating surfaces of the posterior teeth
  • Occlusion – the way the teeth bite or come together. Occlusions may be normal or abnormal (malocclusion) and are classified as Class I, Class II, or Class III
  • Malocclusion – any deviation from a physiologically acceptable relationship of the upper and lower teeth with each other
  • Orthodontics – The dental specialty and practice of preventing and correcting irregularities of the teeth, as by the use of braces
  • Osteotomy – The incision, sectioning, or cutting of a bone, without removing any of its parts, for the purpose of repositioning it into a structurally correct location with itself and adjacent structures (bone cut)
  • Ostectomy – The excision, sectioning, or cutting of a bone for the purpose of removing a portion of the bone and repositioning it into a more structurally balanced relationship with itself and adjacent structures (bone removal)
  • Osteoplasty – A surgical procedure that is designed to change or modify the shape or configuration of a bone (bone graft)
  • Prognathia – an abnormally large mandible or lower jaw
  • Prosthodontics – the dental specialty concerned with the making of artificial replacements for missing parts of the mouth and jaw -- called also prosthetic dentistry, prosthodontia
  • Retrognathia – a posteriorly positioned mandible, or lower jaw; most common problem for which orthognathic surgery is performed (sometimes referred to over bite)
  • Sibilant sound distortions - children with repaired clefts that involve the gum ridge (alveolar ridge) will distort the sounds "s  z  ch  j (as in “judge”) sh zh."  These sounds are called "sibilants."
  • Velopharyngeal distortion - pertaining to the soft palate (velum palatinum) and the pharyngeal walls


The American Association of Oral and Maxillofacial Surgeons (AAOMS) has published Criteria for Orthognathic Surgery (2008), which relate verifiable clinical measurements to significant facial skeletal deformities:

  • Anteroposterior discrepancies
    • Maxillary/Mandibular incisor relationship: overjet of 5 mm or more, or a 0 to a negative value (norm 2 mm).
    • Maxillary/Mandibular anteroposterior molar relationship discrepancy of 4 mm or more (norm 0 to 1 mm).
    • These values represent two or more standard deviation from published norms.
  • Vertical discrepancies
    • Presence of a vertical facial skeletal deformity which is two or more standard deviations from published norms for accepted skeletal landmarks.
    • Open Bite
      • No vertical overlap of anterior teeth.
      • Unilateral or bilateral posterior open bite greater than 2mm.
    • Deep overbite with impingement or irritation of buccal or lingual soft tissues of the opposing arch.
    • Supraeruption of a dentoalveolar segment due to lack of occlusion.
  • Transverse discrepancies
    • Presence of a transverse skeletal discrepancy which is two or more standard deviations from published norms.
    •  Total bilateral maxillary palatal cusp to mandibular fossa discrepancy of 4 mm or greater, or a unilateral discrepancy of 3 mm or greater, given normal axial inclination of the posterior teeth.
  •  Asymmetries
    • Anteroposterior, transverse or lateral asymmetries greater than 3mm with concomitant occlusal asymmetry.

The 2008 AAOMS criteria also has the following position on orthognathic surgery for facial skeletal discrepancies associated with documented speech impairments:  “Abnormal jaw relationships affect many of the structures involved in the production of speech, including the position of the lips, tongue and soft palate.  Studies demonstrate the altered speech production may be associated with facial skeletal deformities, the most common impairment of which is a distortion within the sibilant sound class.  Such studies also demonstrate the beneficial effects of orthognathic surgery on speech production, documenting improvement in a high percentage of patients after the correction of abnormal jaw relationships.  In the age of information, the ability to accurately communicate with an articulate speech pattern is of great importance.  Prior to surgery, speech evaluation should be obtained to demonstrate the nature of the problem and to determine if improvement can be expected.”  A 2004 study by, Janulewicz et al. “…confirmed previous findings that patients with clefts of the lip and palate or palate alone are predisposed to velopharyngeal function alteration after maxillary advancement, particularly with borderline function preoperatively.  However, the results show that surgical correction of skeletal relationships and occlusion may translate into improvement in certain aspects of speech disorders.”

Risk factors for postoperative complications are many, including underlying medical condition, bleeding dyscrasias, factors that affect normal wound healing, a patient with unrealistic expectations, a noncompliant patient, and patients with poor oral hygiene.   In addition, preoperative examination and evaluation are critical aspects of orthognathic surgery.  The outcome of the surgical procedure depends on many factors before, during, and after treatment, as the success of each phase of treatment depends on the success of the preceding phase.  There exists a potential for relapse even in the most ideal situations 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.  Maxillary and mandibular advancements are inherently less stable.  Given these factors, the decision to proceed with orthognathic surgery should be made with caution, and should be made to correct functional impairment.


Disclaimer for coding information on Medical Policies        

Procedure and diagnosis codes on Medical Policy documents are included only as a general reference tool for each policy. They may not be all-inclusive.           

The presence or absence of procedure, service, supply, device or diagnosis codes in a Medical Policy document has no relevance for determination of benefit coverage for members or reimbursement for providers. Only the written coverage position in a medical policy should be used for such determinations.           

Benefit coverage determinations based on written Medical Policy coverage positions must include review of the member’s benefit contract or Summary Plan Description (SPD) for defined coverage vs. non-coverage, benefit exclusions, and benefit limitations such as dollar or duration caps.

ICD-9 Codes

Refer to the ICD-9-CM Manual

ICD-10 Codes

Refer to the ICD-9-CM Manual

Procedural Codes: 21085, 21125, 21127, 21141, 21142, 21143, 21145, 21146, 21147, 21150, 21151, 21154, 21155, 21159, 21160, 21188, 21193, 21194, 21195, 21196, 21198, 21199, 21206, 21208, 21209, 21210, 21215, 21110, 21230, S8262
  1. Proffit WR, White RP Jr.  Who needs surgical-orthodontic treatment?  Int J Adult Orthodon Orthognath Surg 1990; 5(2):81-9.
  2. Vallino LD.  Speech, velopharyngeal function, and hearing before and after orthognathic surgery.
  3.  J Oral Maxillofac Surg 1990 Dec;48(12):1274-81; discussion 1281-2.
  4. Throckmorton GS, Ellis E 3rd, Sinn DP.  Functional characteristics of retrognathic patients before and after mandibular advancement surgery.  J Oral Maxillofac Surg. 1995 Aug; 53(8):898-908; discussion 908-9.
  5. Throckmorton GS, Buschang PH, Ellis E 3rd.  Morphologic and biomechanical determinants in the selection of orthognathic surgery procedures.  J Oral Maxillofac Surg 1999 Sep; 57(9):1044-56; discussion 1056-7.
  6. Janulewicz, J., Costello, B.J., et al.  The effects of Le Fort I osteomoties on velopharyngeal and speech functions in cleft patients.  J Oral Maxillofac Surg (2004 March) 62(3):308-14.Patel, eMedicine - K.P., and A. Gassman.  Craniofacial, Orthognathic Surgery.  eMedicine Specialties (2006 September 6). Available at (accessed 2008 December 1).
  7. The American Association of Oral and Maxillofacial Surgeons.  Criteria for orthognathic surgery.  Rosemont, IL 2008 Available at (accessed 2008 December 1).
  8. The American Association of Oral and Maxillofacial Surgeons.  Guidelines to the evaluation of impairment of the oral and maxollifacial region.  Rosemont, IL 2008 Available at (accessed June 2012).
April 2013  new 2013 BCBSMT medical policy. 
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Orthognathic Surgery