This document addresses medically necessary, reconstructive and cosmetic procedures involving the mandible, maxilla or both, with the exception of orthognathic surgery for the treatment of temporomandibular disorders or obstructive sleep apnea. This document does not apply to orthodontia (braces) services.

Note: Please see the following related documents for additional information:

• MED.00054 Treatment for Obstructive Sleep Apnea in Adults
• CG-SURG-09 Temporomandibular Disorders

Medically Necessary: In this document, procedures are considered medically necessary if there is a significant physical functional impairment AND the procedure can be reasonably expected to improve the physical functional impairment. Some situations where various procedures are considered medically necessary are described below.

Reconstructive: In this document, procedures are considered reconstructive when intended to address a significant variation from normal related to accidental injury, disease, trauma, treatment of a disease or congenital defect. 
Note: Not all benefit contracts include benefits for reconstructive services as defined by this document. Benefit language supersedes this document.

Cosmetic: In this document, procedures are considered cosmetic when intended to change a physical appearance that would be considered within normal human anatomic variation. Cosmetic services are often described as those which are primarily intended to preserve or improve appearance. Some situations where various procedures are considered cosmetic are described below.

Medically Necessary:

Orthognathic surgery is considered medically necessary to treat a significant physical functional impairment when the procedure can be reasonably expected to improve the physical functional impairment. Significant physical functional impairment includes any one of the following:

1. Dysphagia when all of the following criteria (a, b and c) are met:
   1. Symptoms related to difficulty chewing such as: choking due to incomplete mastication, or difficulty swallowing chewed solid food, or ability to chew only soft food or reliance on liquid food; and
   2. Symptoms must be documented in the medical record, must be significant and must persist for at least 4 months; and
   3. Other causes of swallowing or choking problems have been ruled out by history, physical exam and appropriate diagnostic studies.
      OR
2. Speech abnormalities determined by a speech pathologist or therapist to be due to a malocclusion and not helped by orthodontia or at least six months of speech therapy.
   OR 
3. Intra-oral trauma while chewing related to malocclusion (e.g., loss of food through the lips during mastication, causing recurrent damage to the soft tissues of the mouth during mastication).
   OR
4. Masticatory dysfunction or malocclusion as documented by both I and II below:
   1. Completion of skeletal growth with long bone x-ray or serial cephalometrics showing no change in facial bone relationships over the last three to six month period (Class II malocclusions and individuals age 18 and over do not require this documentation); and
   2. Documentation of malocclusion with either intra-oral casts (if applicable) bilateral, lateral x-rays, cephalometric radiograph with measurements, panoramic radiograph or tomograms.

And ANY one of the following described in A, B, C or D:

1. Anteroposterior discrepancies of greater than 2 standard deviations from published norms defined as either of the following:
   • Maxillary/Mandibular incisor relationship: overjet of 5mm or more, or a value less than or equal to zero (norm 2mm). (Note: Overjet up to 5mm may be treatable with routine orthodontic therapy); or
   • Maxillary/Mandibular anteroposterior molar relationship discrepancy of 4mm or more (norm 0 to 1mm).
2. Vertical discrepancies defined as any of the following:
   • Presence of a vertical facial skeletal deformity which is two or more standard deviations from published norms for accepted skeletal landmarks; or
   • Open bite (defined as one of the following):
     1. No vertical overlap of anterior teeth; or
     2. Unilateral or bilateral posterior open bite greater than 2mm; or
   • Deep overbite with impingement or irritation of buccal or lingual soft tissues of the opposing arch; or
   • Supra-eruption of a dentoalveolar segment due to lack of occlusion.
3. Transverse discrepancies defined as either of the following:
   • 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 4mm or greater, or a unilateral discrepancy of 3mm or greater, given normal axial inclination of the posterior teeth.
4. Asymmetries defined as the following:
   • Anteroposterior, transverse or lateral asymmetries greater than 3mm with concomitant occlusal asymmetry

When the condition involves treatment of skeletal deformity, the deformity must be documented either by computed tomography (CT), magnetic resonance imaging (MRI), or x-ray.

Reconstructive:

Orthognathic surgery is considered reconstructive when a significant physical functional impairment is not present, but when there is a significant variation in the normal anatomy of the maxilla and mandible.

Cosmetic and Not Medically Necessary:

Procedures intended to change a physical appearance that would be considered within normal human anatomic variation are considered cosmetic and not medically necessary.

A genioplasty (or anterior mandibular osteotomy) not associated with masticatory malocclusion is considered cosmetic and not medically necessary.

There is convincing evidence of the relationship between facial skeletal abnormalities and malocclusions, including Class II, Class III and open bite deformities. A strong correlation has been demonstrated between the state of the individual's occlusion and his or her chewing efficiency, bite forces and restricted mandibular excursions. Orthognathic surgery has resulted in significant improvement in skeletal deformities that contribute to chewing, breathing and swallowing dysfunction and where the severity of the deformity cannot be corrected through dental therapeutics or orthodontics. Studies have shown that individuals with skeletal malocclusions suffer from a variety of functional impairments including diminished bite forces, restricted mandibular excursions and abnormal chewing patterns. The evidence to support this conclusion includes non-randomized controlled trials and case series studies.

Orthognathic surgery is the surgical correction of skeletal anomalies or malformations involving the mandible (lower jaw) or the maxilla (upper jaw). These malformations may be present at birth or they may become evident as the individual grows and develops. Orthognathic surgery can be performed to correct malocclusion, which cannot be improved with routine orthodontic therapy and where the functional impairments are directly caused by the malocclusion. The overall goal of treatment is to improve function through correction of the underlying skeletal deformity. The American Association of Oral and Maxillofacial Surgeons' classification of occlusion/malocclusion is as follows:

• Class I occlusion: Exists with the teeth in a normal relationship when the mesial-buccal cusp of the maxillary first permanent molar coincides with the buccal groove of the mandibular first molar
• Class II malocclusion: Occurs when the mandibular teeth are distal or 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, and therefore, presents two types: (1) Division I is when the mandibular arch is behind the upper jaw with a consequential protrusion of the upper front teeth. (2) Division II exists when the mandibular teeth are behind the upper teeth, with a retrusion of the maxillary front teeth. Both of these malocclusions have a tendency toward a deep bite because of the uncontrolled migration of the lower front teeth upwards
• Class III malocclusion: Occurs when the lower dental arch is in front of (mesial to) the upper dental arch. People with this type of occlusion usually have a strong or protrusive chin, which can be due to either horizontal mandibular excess or horizontal maxillary deficiency. Commonly referred to as an under bite

Maxillary advancement is a type of orthognathic surgery that may be necessary to improve the facial contour and normalize dental occlusion when there is a relative deficiency of the midface region. This is done by surgically moving the maxilla with sophisticated bone mobilization techniques and fixing it securely into place.

Depending on the soft tissue profile of the face or the severity of an occlusal discrepancy, problems with the lower face may require surgery on the mandible. This can be done in conjunction with or separate from maxillary surgery. The mandible can be advanced, set back, tilted or augmented with bone grafts. A combination of these procedures may be necessary. Following any significant surgical movement of the mandible, fixation may be accomplished with mini-plates and screws or with a combination of interosseous wires and intermaxillary fixation (IMF). Rigid fixation (screws and plates) has the advantage of needing limited or no IMF. However, if interosseous wiring is used, IMF is maintained for approximately six weeks.

Anomaly: Deviation from normal.

Anteroposterior: From front to back.

Asymmetry: The lack of balance or symmetry.

Cephalometric: A scientific measurement of the head.

Cephalometrics: The interpretation of lateral skull x-rays taken under standardized conditions.

Dentoalveolar: Relating to a tooth and the part of the alveolar bone that immediately surrounds it.

Dysphagia: Difficulty swallowing.

Genioplasty: Plastic surgery of the chin.

Malformation: An abnormal shape or structure.

Malocclusion: Imperfect contact with the mandibular and maxillary teeth.

Mandible: The horseshoe-shaped bone forming the lower jaw.

Mastication: Biting and grinding food in the mouth so it becomes soft enough to swallow.

Maxilla: A paired bone that forms the skeletal base of the upper face, roof of the mouth, sides of the nasal cavity and floor of the orbit (contains the eye). The upper jaw.

Occlusion: Bringing the opposing surfaces of the teeth of the two jaws (mandible and maxilla) into contact with each other.

Orthodontics: The division of dentistry dealing with the prevention and correction of abnormally positioned or aligned teeth.

Panoramic radiograph: Radiograph of the maxilla and mandible extending from the left to right glenoid fossa. An x-ray image of a curved body surface, such as the upper and lower jaws, on a single film.

Radiograph: X-ray.

Supraeruption: The occurrence of a tooth continuing to grow out of the gum if the opposing tooth in the opposite jaw is missing.

Tomogram: An image of a tissue section produced by tomography.

Tomography: Imaging by sections or sectioning, through the use of any kind of penetrating wave.

The following codes for treatments and procedures applicable to this document are included below for informational purposes. Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy. Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member. 

When services may be Medically Necessary when criteria are met:

When Services are Reconstructive:
For the procedure codes listed above, when criteria for physical functional impairment is not met; or when the code describes a procedure indicated in the Position Statement section as reconstructive. 

When services are Cosmetic and Not Medically Necessary:For the procedure codes listed above, when criteria are not met, or when the code describes a procedure indicated in the Position Statement section as cosmetic and not medically necessary.

Future ICD-10 coding (effective 10/01/2013)
A draft of ICD-10 Coding related to this document, as it might look today, is available for reference and comments at: Appendix 1: Future ICD-10 coding

Peer Reviewed Publications:

1. Aghabeigi B, Hiranaka D, Keith DA, et al. Effect of orthognathic surgery on the temporomandibular joint in patients with anterior open bite. Int J Adult Orthodon Orthognath Surg. 2001; 16(2):153-160.
2. Ahn SJ, Kim JT, Nahm DS. Cephalometric markers to consider in the treatment of Class II Division 1 malocclusion with the bionator. Am J Orthod Dentofacial Orthop. 2001; 119(6):578-586.
3. Cheung LK, Lo J. The long-term clinical morbidity of mandibular step osteotomy. Int J Adult Orthod Orthognath Surg. 2002; 17(4):283-290.
4. Han H, Davidson WM. A useful insight into 2 occlusal indexes: HLD(Md) and HLD(CalMod). Am J Orthod Dentofacial Orthop. 2001; 120(3):247-253.
5. Incisivo V, Silvestri A. The reliability and variability of SN and PFH reference planes in cephalometric diagnosis and therapeutic planning of dentomaxillofacial malformations. J Craniofacial Surg. 2000; 11(1):31-38.
6. Kim JC, Mascarenhas AK, Joo BH, et al. Cephalometric variables as predictors of Class II treatment outcome. Am J Orthod Dentofacial Orthop. 2000; 118(6):636-640.
7. Mihalik CA, Profitt WR, Phillps C. Long-term follow-up of Class II adults treated with orthodontic camouflage: a comparison with orthognathic surgery outcomes. Am J Orthod Dentofacial Orthop. 2003; 123(3):266-278.
8. Nickel JC, Yao P, Spalding PM, Iwasaki LR. Validated numerical modeling of the effects of combined orthodontic and orthognathic surgical treatment on TMJ loads and muscle forces. Am J Orthod Dentofacial Orthop. 2002; 121(1):73-83.
9. Oguri Y, Yamada K, Fukui T, et al. Mandibular movement and frontal craniofacial morphology in orthognathic surgery patients with mandibular deviation and protrusion. J Oral Rehabil. 2003; 30(4):392-400.
10. Park JE, Baik SH. Classification of angle Class III malocclusion and its treatment modalities. Int J Adult Orthod Orthognath Surg. 2001; 16(1):19-29.
11. Ruf S, Pancherz H. Orthognathic surgery and dentofacial orthopedics in adult Class II Division 1 treatment: mandibular sagittal split osteotomy versus Herbst appliance. Am J Orthod Dentofacial Orthop. 2004; 126(2):140-152.
12. Stellzig-Eisenhauser A, Lux CJ, Schuster G. Treatment decision in adult patients with Class III malocclusion: orthodontic therapy or orthognathic surgery? Am J Orthod Dentofacial Orthop. 2002; 122(1):27-38.
13. Wolford LM, Karras S, Mehra P. Concomitant temporomandibular joint and orthognathic surgery: a preliminary report. J Oral Maxillofac Surg. 2002; 60(4):356-362; discussion 362-363.
14. Wolford LM, Karras SC, Mehra P. Consideration for orthognathic surgery during growth, part 1: mandibular deformities. Am J Orthod Dentofacial Orthop. 2001; 119(2):95-101.
15. Wolford LM, Karras SC, Mehra P. Consideration for orthognathic surgery during growth, part 2: maxillary deformities. Am J Orthod Dentofacial Orthop. 2001; 119(2):102-105.
16. Yamada K, Hanada K, Hayashi T, Ito J. Condylar bony change, disk displacement, and signs and symptoms of TMJ disorders in orthognathic surgery patients. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2001; 91(5):603-610.

Government Agency, Medical Society, and Other Authoritative Publications:

1. American Association of Oral and Maxillofacial Surgeons. Criteria for Orthognathic Surgery. (2008) Available at: http://www.aaoms.org/docs/practice_mgmt/ortho_criteria.pdf. Accessed on May 11, 2011.
2. American Association of Oral and Maxillofacial Surgeons. Guidelines to the evaluation of impairment of the oral and maxillofacial region. (2008). Available at: http://www.aaoms.org/docs/practice_mgmt/impairment_guidelines.pdf. Accessed on May 11, 2011.

Anteroposterior Discrepancies
Asymmetries
Cleft Palate
LeFort Procedure
Malocclusion: Class I, Class II, and Class III
Mandibular/Maxillary Surgery
Maxillofacial Surgery
Orthognathic Surgery
Transverse Discrepancies
Vertical Discrepancies