Orthognathic Surgery

Number: 0095

Table Of Contents

Applicable CPT / HCPCS / ICD-10 Codes


Scope of Policy

This Clinical Policy Bulletin addresses orthognathic surgery.

  1. Medical Necessity

    Certain jaw and cranio-facial deformities may cause significant functional impairment. These deformities include apertognathia (either lateral or anterior not correctable by orthodontics alone), significant asymmetry of the lower jaw, significant class 2 and class 3 occlusal discrepancies, and cleft palate. 

    Aetna considers orthognathic surgery medically necessary for correction of the following skeletal deformities of the maxilla or mandible when it is documented that these skeletal deformities are contributing to significant dysfunction, and where the severity of the deformities precludes adequate treatment through dental therapeutics and orthodontics alone:

    1. Maxillary and/or Mandibular Facial Skeletal Deformities Associated with Masticatory Malocclusion

      For correction of skeletal deformities of the maxilla or mandible when it is documented that these skeletal deformities are contributing to significant masticatory dysfunction, and where the severity of the deformities precludes adequate treatment through dental therapeutics and orthodontics:

      1. Antero-posterior discrepancies
        1. Maxillary/mandibular incisor relationship: overjet of 5 millimeter (mm) or more, or a 0 to a negative value (norm 2 mm);
        2. Maxillary/mandibular antero-posterior molar relationship discrepancy of 4 mm or more (norm 0 to 1 mm).

        Note: These values represent 2 or more standard deviations (SDs) from published norms.

      2. Vertical discrepancies
        1. Presence of a vertical facial skeletal deformity which is 2 or more SDs from published norms for accepted skeletal landmarks;
        2. Open Bite:

          1. No vertical overlap of anterior teeth greater than 2 mm;
          2. Unilateral or bilateral posterior open bite greater than 2 mm;
        3. Deep overbite with impingement or irritation of buccal or lingual soft tissues of the opposing arch;
        4. Supraeruption of a dento-alveolar segment due to lack of opposing occlusion creating dysfunction not amenable to conventional prosthetics.
      3. Transverse discrepancies
        1. Presence of a transverse skeletal discrepancy which is 2 or more SDs  from published norms;
        2. 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.
      4. Asymmetries

        Antero-posterior, transverse or lateral asymmetries greater than 3 mm with concomitant occlusal asymmetry.

    2. Facial Skeletal Discrepancies Associated with Documented Sleep Apnea, Airway Defects, and Soft Tissue Discrepancies

      Aetna considers orthognathic surgery medically necessary for the following:

      1. In cases where it is documented that mandibular and maxillary deformities are contributing to airway dysfunction, where such dysfunction is not amenable to non-surgical treatments, and where it is shown that orthognathic surgery will decrease airway resistance and improve breathing.

        For example, studies demonstrate that persons with vertical hyperplasia of the maxilla have an associated increase in nasal resistance, as do persons with maxillary hypoplasia with or without clefts. Following orthognathic surgery, such individuals routinely demonstrate decreases in nasal airway resistance and improved respiration.

      2. Members with underlying craniofacial skeletal deformities that are contributing to obstructive sleep apnea. See CPB 0004 - Obstructive Sleep Apnea in Adults.  Before surgery, such individuals should be properly evaluated to determine the cause and site of their disorder and appropriate non-surgical treatments attempted when indicated.

    3. Speech Impairments

      Aetna considers orthognathic surgery medically necessary for treatment of speech impairments accompanying severe cleft deformity. Orthognathic surgery may help to reduce the flattening of the face that is characteristic of severe cleft deformity.  By using osteotomy techniques along with bone and cartilage grafts, the upper and lower jaws and facial skeletal framework are moved and appropriately reconstructed.  Pre-surgical orthodontic treatment is usually recommended.

      Aetna considers orthognathic surgery for correction of distortions within the sibilant sound class or for other distortions of speech quality (e.g., hyper-nasal or hypo-nasal speech) not medically necessary as these distortions do not cause functional impairment.

    Aetna considers orthognathic surgery experimental, investigational, or unproven for all indications other than those listed above because their effectiveness for indications other than the ones listed above has not been established.

    Note: Precertification requests or claims for orthognathic surgery are subject to review by Aetna's Oral and Maxillofacial Surgery Unit.

    Documentation Requirements

    Note: Orthognathic surgery may be subject to precertification review in plans that include precertification requirements.  The following documentation should be forwarded to Aetna's Oral and Maxillofacial Surgery Unit for review:

    1. A written explanation of the member's clinical course, including dates and nature of any previous treatment;
    2. Physical evidence of a skeletal, facial or craniofacial deformity defined by study models and pre-orthodontic imaging; and 
    3. A detailed description of the functional impairment considered to be the direct result of the skeletal abnormality.
  2. Experimental, Investigational, or Unproven

    1. Aetna considers orthognathic surgeries other than those identified in section I.C. for correction of articulation disorders and other impairments in the production of speech experimental, investigational, or unproven because there is inadequate evidence from prospective clinical studies in the peer-reviewed published medical literature of the effectiveness of orthognathic surgery for this indication.
    2. The following are considered experimental, investigational, or unproven because the effectiveness has not been established:

      1. Temporomandibular joint pathology - orthognathic surgery for correction of temporomandibular joint disease or myofascial pain dysfunction (see CPB 0028 - Temporomandibular Disorders);
      2. Condylar positioning devices in orthognathic surgery;
      3. Low-level laser therapy for the management of neurosensory disorders and post-operative edema, pain/paresthesia following orthognathic surgery;
      4. Manual lymphatic drainage for the management of post-operative edema following orthognathic surgery;
      5. Patient-specific non-biodegradable osteosynthesis for orthognathic surgery. Note: Aetna considers the use of biodegradable osteosyntheses as a supply in orthognathic surgery;
      6. Three-dimensional virtual treatment planning or computer-aided three-dimensional simulation and navigation in orthognathic surgery (CASNOS);
      7. Use of Kinesio taping for reduction of swelling in persons after orthognathic surgery.
  3. Cosmetic

    Unaesthetic Facial Features and Psychological Impairments

    1. Aetna considers orthognathic surgery cosmetic for correction of unaesthetic facial features, regardless of whether these are associated with psychological disorders.
    2. Mentoplasty or genial osteotomies/ostectomies (chin surgeries) are always considered cosmetic when performed as an isolated procedure to address genial hypoplasia, hypertrophy, or asymmetry, and may be considered cosmetic when performed with other surgical procedures.
    3. No benefits are available for orthognathic surgery performed primarily for cosmetic purposes.  See Aetna CPB 0031 - Cosmetic Surgery.
  4. Plan Limitations and Exclusions

    Orthodontic Treatment Prior to Orthognathic Surgery

    Note: Expenses associated with the orthodontic phase of care (both pre- and post-surgical) are considered dental in nature and are not covered under Aetna's medical plans.  See CPB 0082 - Dental Services and Oral and Maxillofacial Surgery: Coverage Under Medical Plans.

    Orthodontic treatment may be needed prior to orthognathic surgery to position the teeth in a manner that will provide for an adequate occlusion following surgical repositioning of the jaws.  For plans that require precertification, orthognathic surgery must be precertified prior to pre-surgical orthodontic treatment.  The interim occlusion that is achieved by orthodontic treatment may be dysfunctional prior to the completion of the orthognathic surgical phase of the treatment plan.  Therefore, all requests for orthognathic surgery must be reviewed/precertified by an the Aetna Oral and Maxillofacial Surgery Unit prior to the initiation of pre-surgical orthodontic care. Failure to obtain precertification of orthognathic surgery prior to orthodontic care may result in the denial of benefits.

    See also CPB 0082 - Dental Services and Oral and Maxillofacial Surgery: Coverage Under Medical Plans.

  5. Related Policies

    1. CPB 0004 - Obstructive Sleep Apnea in Adults
    2. CPB 0028 - Temporomandibular Disorders
    3. CPB 0031 - Cosmetic Surgery
    4. CPB 0082 - Dental Services and Oral and Maxillofacial Surgery: Coverage Under Medical Plans


CPT Codes / HCPCS Codes / ICD-10 Codes

Code Code Description

CPT codes covered if selection criteria are met:

21083 Impression and custom preparation; palatal lift prosthesis
21084     speech aid prosthesis
21085     oral surgical splint
21088     facial prosthesis
21141 Reconstruction midface, Lefort I; single piece, segment movement in any direction (e.g., for Long Face Syndrome), without bone graft
21142     2 pieces, segment movement in any direction, without bone graft
21143     3 or more pieces, segment movement in any direction, without bone graft
21145     single piece, segment movement in any direction, requiring bone grafts (includes obtaining graft)
21146     2 pieces, segment movement in any direction, requiring bone grafts (includes obtaining autografts) (e.g., ungrafted unilateral alveolar cleft)
21147     3 or more pieces, segment movement in any direction, requiring bone grafts (includes obtaining autografts) (e.g., ungrafted bilateral alveolar cleft or multiple osteotomies)
21150 Reconstruction midface, Lefort II; anterior intrusion (e.g., Treacher-Collins Syndrome)
21151     any direction, requiring bone grafts (includes obtaining autografts)
21154 Reconstruction midface, Lefort III (extracranial), any type, requiring bone grafts (includes obtaining autografts); without Lefort I
21155     with Lefort I
21159 Reconstruction midface, Lefort III (extra and intracranial) with forehead advancement (e.g., mono bloc), requiring bone grafts (includes obtaining autografts): without Lefort I
21160     with Lefort I
21181 Reconstruction by contouring of benign tumor of cranial bones (e.g., fibrous dysplasia), extracranial
21182 Reconstruction of orbital walls, rims, forehead, nasoethmoid complex following intra- and extracranial excision of benign tumor of cranial bone (e.g., fibrous dysplasia) with multiple autografts (includes obtaining grafts); total area of bone grafting less than 40 sq cm
21183     total area of bone grafting greater than 40 sq cm but less than 80 sq cm
21184     total area of bone grafting greater than 80 sq cm
21188 Reconstruction midface, osteotomies (other than Lefort type) and bone grafts (includes obtaining autografts)
21193 Reconstruction of mandibular rami, horizontal, vertical, C, or L osteotomy; without bone graft
21194     with bone graft (includes obtaining graft)
21195 Reconstruction of mandibular rami and/or body, sagittal split; without internal rigid fixation
21196     with internal rigid fixation
21198 Osteotomy, mandible, segmental;
21199     with genioglossus advancement
21206 Osteotomy, maxilla, segmental (e.g., Wassmund or Schuchard)
21208 Osteoplasty, facial bones; augmentation (autograft, allograft, or prosthetic implant)
21209     reduction
21210 Graft, bone; nasal, maxillary or malar areas (includes obtaining graft)
21215     mandible (includes obtaining graft)
21230 Graft; rib cartilage, autogenous, to face, chin, nose or ear (includes obtaining graft)
21235     ear cartilage, autogenous, to nose or ear (includes obtaining graft)
21240 Arthroplasty, temporomandibular joint, with or without autograft (includes obtaining graft)
21242 Arthroplasty, temporomandibular joint, with allograft
21243 Arthroplasty, temporomandibular joint, with prosthetic joint replacement
21247 Reconstruction of mandibular condyle with bone and cartilage autografts (includes obtaining grafts) (e.g., for hemifacial microsomia)
21255 Reconstruction of zygomatic arch and glenoid fossa with bone and cartilage (includes obtaining autografts)
21270 Malar augmentation, prosthetic material
21275 Secondary revision of orbitocraniofacial reconstruction
21295 Reduction of masseter muscle and bone (e.g., for treatment of benign masseteric hypertrophy); extraoral approach
21296     intraoral approach
42200 - 42281 Repair of palate

CPT codes not covered for indications listed in the CPB:

Computer-aided three-dimensional simulation and navigation in orthognathic surgery (CASNOS), Patient specific osteosynthesis - no specific code
0552T Low-level laser therapy, dynamic photonic and dynamic thermokinetic energies, provided by a physician or other qualified health care professional
21125 Augmentation, mandibular body or angle; prosthetic material
21127     with bone graft, onlay or interpositional (includes obtaining autograft)
97140 Manual therapy techniques, 1 or more regions, each 15 minutes (Mobilization/manipulation, manual lymphatic drainage, manual traction)

Other CPT codes related to the CPB:

21110 Application of interdental fixation device for conditions other than fracture or dislocation, includes removal
21120 - 21123 Genioplasty

HCPCS codes covered if selection criteria are met:

D5954 - D5959 Palatal augmentation and lift prosthesis
D7940 - D7955 Other repair procedures

HCPCS codes not covered for indications listed in the CPB:

Kinesio taping - no specific code:

D0372 Intraoral tomosynthesis – comprehensive series of radiographic images
D0373 Intraoral tomosynthesis – bitewing radiographic image
D0374 Intraoral tomosynthesis – periapical radiographic image
D0387 Intraoral tomosynthesis – comprehensive series of radiographic images – image capture only
D0388 Intraoral tomosynthesis – bitewing radiographic image – image capture only
D0389 Intraoral tomosynthesis – periapical radiographic image – image capture only
D0801 3D dental surface scan – direct
D0802 3D dental surface scan – indirect
D0803 3D facial surface scan – direct
D0804 3D facial surface scan – indirect

Other HCPCS codes related to the CPB:

C1713 Anchor/screw for opposing bone-to-bone or soft tissue-to-bone (implantable)
C1889 Implantable/insertable device, not otherwise classified
D8010 - D8999 Orthodontics

ICD-10 codes covered if selection criteria are met:

G47.33 Obstructive sleep apnea (adult) (pediatric) [associated with facial skeletal deformities]
M26.00 - M26.59, M26.70 - M26.9 Dentofacial anomalies [including malocclusion] and other disorders of jaw [except TMJ disorders]
Q35.1 - Q37.9 Cleft lip and cleft palate

ICD-10 codes not covered for indications listed in the CPB:

G89.18 Other acute postprocedural pain [neurosensory disorders]
G89.28 Other chronic postprocedural pain [neurosensory disorders]
M26.601 - M26.609 Temporomandibular joint disorders
R20.2 Paresthesia of skin [neurosensory disorders]
R60.0 - R60.9 Edema, not elsewhere classified [Postoperative edema]
Z41.1 Encounter for cosmetic surgery
Z98.890 Other postprocedural states [post orthognathic surgery]


Orthognathic surgery is the revision by ostectomy, osteotomy or osteoplasty of the upper jaw (maxilla) and/or the lower jaw (mandible) intended to alter the relationship of the jaws and teeth.  These surgical procedures are intended

  1. to correct skeletal jaw and cranio-facial deformities that may be associated with significant functional impairment, and
  2. to reposition the jaws when conventional orthodontic therapy alone is unable to provide a satisfactory, functional dental occlusion within the limits of the available alveolar bone. 

Congenital or developmental defects can interfere with the normal development of the face and jaws. These birth defects may interfere with the ability to chew properly, and may also affect speech and swallowing. In addition, trauma to the face and jaws may create skeletal deformities that cause significant functional impairment. Functional deficits addressed by this type of surgery are those that affect the skeletal masticatory apparatus such that chewing, speaking and/or swallowing are impaired. 

During the procedure, an oral and maxillofacial surgeon repositions the affected areas (mentum, mandible and/or maxilla) to approximate normal alignment and structure; sometimes adding, removing or reshaping bone. Synthetic prosthetic materials may be used along with surgical plates, screws, wires and rubber bands to hold the jaws into the new position. The most common surgical technique is known as the LeFort I (though there are variations of this technique that may be performed, depending on the exact indications for the surgery).

There is a lack of evidence to support the use of condylar positioning devices in orthognathic surgery.  Costa et al (2008) stated that in the past few years, many devices have been proposed for preserving the pre-operative position of the mandibular condyle during bilateral sagittal split osteotomy.  The authors stated that accurate mandibular condyle re-positioning is considered important to obtain a stable skeletal and occlusal result, and to prevent the onset of TMD.  Condylar positioning devices (CPDs) have led to longer operating times, the need to keep inter-maxillary fixation as stable as possible during their application, and the need for precision in the construction of the splint or intra-operative wax bite.  The authors reviewed the literature concerning the use of CPDs in orthognathic surgery since 1990 and their application to prevent skeletal instability and contain TMD since 1995.  They concluded that there is no scientific evidence to support the routine use of CPDs in orthognathic surgery.

Stokbro et al (2014) stated that numerous publications regarding virtual surgical planning protocols have been published, most reporting only 1 or 2 case reports to emphasize the hands-on planning.  None had systematically reviewed the data published from clinical trials.  This systematic review analyzed the precision and accuracy of three-dimensional (3D) virtual surgical planning of orthognathic procedures compared with the actual surgical outcome following orthognathic surgery reported in clinical trials.  These researchers performed a systematic search of the current literature to identify clinical trials with a sample size of more than 5 patients, comparing the virtual surgical plan with the actual surgical outcome.  Search terms revealed a total of 428 titles, out of which only 7 articles were included, with a combined sample size of 149 patients.  Data were presented in 3 different ways: intra-class correlation coefficient, 3D surface area with a difference less than 2mm, and linear and angular differences in 3D.  Success criteria were set at 2 mm mean difference in 6 articles; 125 of the 133 patients included in these articles were regarded as having had a successful outcome.  Due to differences in the presentation of data, meta-analysis was not possible.  The authors concluded that virtual planning appears to be an accurate and reproducible method for orthognathic treatment planning; a more uniform presentation of the data is necessary to allow the performance of a meta-analysis.  Moreover, they stated that currently the software system most often used for 3D virtual planning in clinical trials is SimPlant (Materialise); more independent clinical trials are needed to further validate the precision of virtual planning.

Adolphs et al (2014) stated that within the domain of craniomaxillofacial surgery, orthognathic surgery is a special field dedicated to the correction of dentofacial anomalies resulting from skeletal malocclusion.  Generally, in such cases, an inter-disciplinary orthodontic and surgical treatment approach is needed.  After initial orthodontic alignment of the dental arches, skeletal discrepancies of the jaws can be corrected by distinct surgical strategies and procedures in order to achieve correct occlusal relations, as well as facial balance and harmony within individualized treatment concepts.  To transfer the pre-operative surgical planning and re-position the mobilized dental arches with optimal occlusal relations, surgical splints are typically used.  For this purpose, different strategies have been described which use 1 or more splints.  Traditionally, these splints are manufactured by a dental technician based on patient-specific dental casts; however, computer-assisted technologies have gained increasing importance with respect to pre-operative planning and its subsequent surgical transfer.  In a pilot study of 10 patients undergoing orthognathic corrections by a 1-splint strategy, 2 final occlusal splints were produced for each patient and compared with respect to their clinical usability. One splint was manufactured in the traditional way by a dental technician according to the preoperative surgical planning. After performing a CBCT scan of the patient's dental casts, a second splint was designed virtually by an engineer and surgeon working together, according to the desired final occlusion.  For this purpose, RapidSplint, a custom-made software platform, was used.  After post-processing and conversion of the datasets into .stl files, the splints were fabricated by the PolyJet procedure using photo polymerization.  During surgery, both splints were inserted after mobilization of the dental arches then compared with respect to their clinical usability according to the occlusal fitting.  Using the workflow described above, virtual splints could be designed and manufactured for all patients in this pilot study.  Eight of 10 virtual splints could be used clinically to achieve and maintain final occlusion after orthognathic surgery.  In 2 cases virtual splints were not usable due to insufficient occlusal fitting, and even two of the traditional splints were not clinically usable. In five patients where both types of splints were available, their occlusal fitting was assessed as being equivalent, and in one case the virtual splint showed even better occlusal fitting than the traditional splint.  In 1 case where no traditional splint was available, the virtual splint proved to be helpful in achieving the final occlusion.  The authors concluded that the findings of this pilot study demonstrated that clinically usable splints for orthognathic surgery can be produced by computer-assisted technology.  Virtual splint design was realized by RapidSplint®, an in-house software platform which might contribute in future to shorten pre-operative workflows for the production of orthognathic surgical splints.  The preliminary findings from this pilot study need to be validated by well-designed studies.

Swennen (2014) evaluated the timing for 3D virtual treatment planning of orthognathic surgery in the daily clinical routine.  A total of 350 consecutive patients were included in this study.  All patients were scanned following the standardized "Triple CBCT Scan Protocol" in centric relation.  Integrated 3D virtual planning and actual surgery were performed by the same surgeon in all patients.  The authors concluded that although clinically acceptable, still software improvements especially toward 3D virtual occlusal definition are mandatory to make 3D virtual planning of orthognathic surgery less time-consuming and more user-friendly to the clinician.

Austin et al (2015) compared the effectiveness of distraction osteogenesis to orthognathic surgery (OS) for the treatment of maxillary hypoplasia in individuals with cleft lip and palate.  These investigators performed a systematic review of prospective randomized, quasi-randomized or controlled clinical trials.  Medline, Embase, Scopus, Web of Science, CINAHL, CENTRAL, trial registers and grey literature were searched.  Hand-searching of 5 relevant journals was completed.  Two reviewers independently completed inclusion assessment.  Data extraction and risk of bias assessment were completed by a single reviewer and checked by a second reviewer.  A total of 5 publications all reporting different outcomes of a single RCT were included within the review.  The quality of the evidence was low with a high risk of bias.  Both surgical interventions produced significant soft tissue improvement.  Horizontal relapse of the maxilla was statistically significantly greater following OS.  There was no statistically significant difference in speech and velo-pharyngeal function between the interventions.  Maxillary distraction initially lowered social self-esteem, but this improved with time resulting in higher satisfaction with life in the long-term.  The authors concluded that the low quality of evidence included within the review meant there is insufficient evidence to conclude whether there is a difference in effectiveness between maxillary distraction and osteotomy for the treatment of cleft-related maxillary hypoplasia.  They stated that there is a need for further high-quality RCTs to allow conclusive recommendations to be made.

Olsen et al (2016) evaluated the effectiveness of hemostatic adjuncts on intra-operative blood loss (IOBL) in OS detected by RCTs of the highest quality.  A search of the Medline, Cochrane, Embase, and Web of Science databases was performed in January 2015, and the risk of bias was assessed using the Jadad and Delphi scales.  The predictor variable was the hemostatic measures, and the main outcome variable was the total IOBL volume.  The secondary outcome variables were the hemoglobin and hematocrit and operating time.  A total of 11 trials were included for review.  The individual trials demonstrated the effects on IOB from hypotensive anesthetic regimens, the use of aprotinin, and the herbal medicine Yunnan Baiyao.  Six studies of tranexamic acid (TXA), with 288 patients, were suitable for a meta-analysis of continuous data.  Tranexamic acid reduced IOBL by an average of 171 ml (95 % confidence interval [CI]: -230 to -112; p < 0.00001).  Its topical use yielded similarly significant results (mean difference -197, 95 % CI: -319 to -76; p < 0.001).  A subgroup analysis showed a decreased operating time in the TXA groups by an average of 15 minutes (mean difference -14.78, 95 % CI: -22.21 to -7.35; p < 0.0001).  The authors concluded that efficient hemostatic adjuncts exist for OS.  The findings of this meta-analysis showed that TXA significantly reduced IOBL by an average of 1/3, regardless of whether it was given intravenously (IV) or applied topically.  They stated that additional RCTs are needed to confirm the effect of topical TXA in OS, and larger studies of intravenous administration are needed before any routine recommendations.  No hemostatic effect of hypotensive anesthesia was found, mainly owing to imprecise descriptions of the blinding procedures.  Transparent and uniform trial reporting is thus encouraged in future studies.

Borba and colleagues (2016) stated that the sequencing of bi-maxillary orthognathic surgery remains controversial, although the traditional maxilla-first approach is performed routinely.  The se investigators presented a systematic review of the mandible-first sequence in bi-maxillary orthognathic surgery, provided data that may assist in the decision as to which jaw should undergo osteotomy first in bi-maxillary orthognathic surgery cases.  A literature search was conducted for articles published in the English language, reporting the use of the altered sequence for bi-maxillary orthognathic surgery (mandible-first), using the following descriptors: “orthognathic” and “double-jaw”, “orthognathic” and “two-jaw”, “orthognathic” and “mandible-first”, “orthognathic” and “bi-maxillary”.  A total of 887 abstracts were initially identified and were evaluated for inclusion according to the proposed inclusion criteria.  After evaluation of these abstracts and relevant references, 6 publications met the criteria for consideration.  Performing mandible-first surgery in bi-maxillary orthognathic cases dated back to the 1970s; however the decision regarding the jaw to be operated on first appeared to rely on accurate pre-operative planning based upon the surgeon's experience and preference.  While there appeared to be significant theoretical advantages to support the use of the altered orthognathic sequence (mandible-first), future prospective studies on its reliability, accuracy, and short- and long-term outcomes are needed.

Posnick et al (2016) examined operative time, peri-operative airway management, early post-operative cardio-pulmonary health, need for blood transfusion, and in-hospital stay associated with simultaneous bi-maxillary, intra-nasal, and osseous genioplasty surgery.  These investigators performed a retrospective cohort study derived from patients treated by 1 surgeon at a single institution from 2009 through 2014.  The sample consisted of a consecutive series of patients with symptomatic chronic obstructed nasal breathing and a dento-facial deformity (DFD).  All underwent at least a Le Fort I osteotomy, sagittal ramus osteotomies, septoplasty, inferior turbinate reduction, and osseous genioplasty.  For each patient, the design of the osteotomies and the fixation techniques were consistent.  The outcome variables included need for blood transfusion, operating time, success of naso-tracheal intubation, time and place of extubation, early post-operative cardio-pulmonary health, length of in-hospital stay, and need for re-admission after surgery.  For the 166 patients studied, the average age was 25 years (range of 13 to 65; 87 female patients [52 %]).  The primary patterns of presenting DFD included long face (43 of 166, 26 %), maxillary deficiency (41 of 166, 25 %), asymmetric mandibular excess (37 of 166, 22 %), short face (28 of 166, 17 %), and mandibular deficiency (15 of 166, 9 %); 42 patients (25 %) were confirmed to have symptomatic obstructive sleep apnea (OSA).  The open wound operating time averaged 2 hours 59 minutes (SD = 32 minutes).  Only 3 of the 166 patients (1.8 %) received blood transfusions.  All patients underwent successful naso-tracheal intubation; 96 % of patients were extubated in the operating room and the remaining 4 % were extubated in the recovery room.  No patients required re-intubation or tracheostomy; 137 patients (83 %) were discharged after a 1- or 2-night in-hospital stay; 25 (15 %) required a 3-night stay; and 4 (2 %) required a 4-night hospital stay to achieve adequate oral intake; none of the patients required re-admission.  The authors concluded that the findings of this study confirmed efficient surgical and anesthesia care for patients undergoing simultaneous bi-maxillary orthognathic, intra-nasal, and osseous genioplasty, and anticipating safe naso-tracheal intubation with extubation soon after surgery and a limited need for blood transfusion has proved to be the norm.  They stated that this study confirmed an average in-hospital stay of 2 nights after complex orthognathic surgery without need for re-admission.

Bioresorbable Fixation Following Orthognathic Surgery

Agnihotry and associates (2017) noted that recognition of some of the limitations of titanium plates and screws used for the fixation of bones has led to the development of plates manufactured from bioresorbable materials.  While resorbable plates appear to offer clinical advantages over metal plates in orthognathic surgery, concerns remain about the stability of fixation and the length of time required for their degradation and the possibility of foreign body reactions.  In an update of the Cochrane Review first published in 2007., these investigators compared the effects of bioresorbable fixation systems with titanium systems used during orthognathic surgery.  Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to January 20, 2017); the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 11) in the Cochrane Library (searched January 20, 2017); Medline Ovid (1946 to January 20, 2017); and Embase Ovid (1980 to January 20, 2017).  These investigators searched the US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov (clinicaltrials.gov; searched January 20, 2017), and the World Health Organization International Clinical Trials Registry Platform (searched  January 20, 2017) for ongoing trials.  No restrictions were placed on the language or date of publication when searching the electronic databases; RCTs comparing bioresorbable versus titanium fixation systems used for orthognathic surgery in adults were selected for analysis.  Two review authors independently screened the results of the electronic searches, extracted data and assessed the risk of bias of the included studies.  They resolved disagreement by discussion.  Clinical heterogeneity between the included trials precluded pooling of data, and only a descriptive summary was presented.  This review included 2 trials, involving 103 participants, one comparing titanium with resorbable plates and screws and the other titanium with resorbable screws.  Both studies were at high risk of bias and provided very limited data for the primary outcomes of this review.  All participants in one trial suffered mild-to-moderate post-operative discomfort with no statistically significant difference between the 2 plating groups at different follow-up times.  Mean scores of patient satisfaction were 7.43 to 8.63 (range of 0 to 10) with no statistically significant difference between the 2 groups throughout follow-up.  Adverse effects reported in one study were 2 plate exposures in each group occurring between the 3rd and 9th months.  Plate exposures occurred mainly in the posterior maxillary region, except for 1 titanium plate exposure in the mandibular premolar region.  Known causes of infection were associated with loosened screws and wound dehiscence with no statistically significant difference in the infection rate between titanium (1.5 % [3/196]), and resorbable (1.8 % [3/165]) plates.  The authors concluded that they did not have sufficient evidence to determine if titanium plates or resorbable plates are superior for fixation of bones after orthognathic surgery.  They stated that this review provided insufficient evidence to show any difference in post-operative pain and discomfort, level of patient satisfaction, plate exposure or infection for plate and screw fixation using either titanium or resorbable materials.

Luo and colleagues (2018) stated that despite developments in bioresorbable fixation over recent decades, controversy remains regarding skeletal stability following the use of this material in orthognathic surgery.  This systematic review and meta-analysis examined evidence from the international literature from studies comparing skeletal stability between bioresorbable and titanium fixation in orthognathic surgery. Key words were searched in Medline, Embase, and Cochrane Library, and relevant journals and reference lists were searched for additional material, up to January 2017.  Study quality was assessed with the Newcastle-Ottawa scale.  The meta-analysis was performed using RevMan software; a total of 10 cohort studies were included.  The meta-analysis showed no statistically significant difference between bioresorbable and titanium fixation (standard mean difference [SMD] (95 % CI)) for maxillary horizontal relapse (maxillary advancement 0.09 (-0.16 to 0.33); maxillary setback -0.04 (-0.64 to 0.56)), maxillary vertical relapse (maxillary elongation 0.15 (-0.31 to 0.61); maxillary impaction -0.30 (-1.10 to 0.50)), mandibular horizontal relapse (mandibular advancement 0.16 (-0.72 to 1.03); short-term mandibular setback -0.33 (-0.82 to 0.15)), and mandibular angular relapse (mandibular clockwise rotation -0.39 (-0.79 to 0.00); mandibular counter-clockwise rotation 0.14 (-0.37 to 0.66)).  However, after mandibular setback, titanium fixation showed significantly less relapse in the long-term (0.97 (0.47 to 1.47)).  The authors concluded that with regard to skeletal stability, bioresorbable fixation was comparable to titanium fixation when used in maxillary setback and mandibular clockwise rotation; however titanium fixation may be preferable in mandibular setback.  Moreover, they stated that further high-quality studies are needed to draw more definitive conclusions.

Low-Level Laser Therapy Following Orthognathic Surgery

In a systematic review, Bittencourt and associates (2017) examined scientific evidence concerning the effectiveness of laser to reduce pain or paresthesia related to orthognathic surgery.  An electronic search was performed in PubMed, Scopus, Science Direct, LILACS, SciELO, CENTRAL, Google Scholar, OpenGrey, and ClinicalTrials.gov, up to November 2016, with no restrictions on language or year of publication.  Additionally, a hand-search of the reference list of the selected studies was performed.  The PICOS strategy was used to define the eligibility criteria and only randomized clinical trials were selected.  Out of 1,257 identified citations, 3 papers fulfilled the criteria and were included in the systematic review.  The risk of bias was assessed according to the Cochrane Guidelines for Clinical Trials and results were exposed based on a descriptive analysis.  One study showed that laser therapy was effective to reduce post-operative pain 24 hours (p = 0.007) and 72 hours (p = 0.007) after surgery.  Other study revealed the positive effect of laser to improve neurosensory recovery 60 days after surgery, evaluated also by the 2-point discrimination (p = 0.005) and sensory (p = 0.008) tests.  The 3rd study reported an improvement for general sensibility of 68.75 % for laser group, compared with 21.43 % for placebo (p = 0.0095), 6 months following surgery.  The authors concluded that individual studies suggested a positive effect of low-level laser therapy on reduction of post-operative pain and acceleration of improvement of paresthesia related to orthognathic surgery.  However, they noted that due to the insufficient number and heterogeneity of studies, a meta-analysis evaluating the outcomes of interest was not performed, and a pragmatic recommendation about the use of laser therapy was not possible.  These investigators stated that further high-quality clinical trials are needed to increase the strength of evidence and to confirm the effectiveness of low-level laser for the treatment of neurosensory disorders after orthognathic surgery.

Alyahya et al (2022) noted that pain management in orthognathic surgery is critical to enhance recovery, reduce hospital length of stay (LOS), and improve the whole experience of the patient.  In a systematic review and meta-analysis, these investigators examined available evidence on pain management in orthognathic surgery.  They carried out a review of the literature following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and PubMed, Embase, and the Cochrane Controlled Trials Registry were searched to retrieve randomized clinical trials (RCTs) published until July 2020.  RCTs that compared different pre-emptive analgesia and LLLT with placebo following orthognathic surgery were included.  Outcome variables were pain scores and duration of surgery.  The quality of evidence was rated according to Cochrane's tool for assessing risk of bias.  Standardized mean difference (SMD) or MD was employed to analyze continuous data.  There was significant pain reduction within the first 48 hours following pre-emptive analgesia (very low quality evidence, SMD: -1.329; CI: -2.030 to -0.628; p = 0.001) and LLLT (very low quality evidence, SMD: -0.690; CI: -1.172 to -0.207; p = 0.005) versus placebo.  The authors concluded that the evidence to support pre-emptive analgesia or LLLT effectively reducing pain scores within the first post-operative 48 hours following orthognathic surgery when compared with placebo, was of low quality.

In a systematic review, Meneses-Santos et al (2022) examined the available evidence of the effect of LLLT on the perception of pain, edema, and trismus following orthognathic surgery.  These investigators carried out a literature in 11 databases (MedLine via PubMed, Scopus, LILACS, SciELO, Embase, Web of Science, Cochrane Library, and LIVIVO, OpenGrey, OADT, and OpenThesis), without restriction of publication year or language.  This search aimed to identify randomized clinical trials comparing LLLT and placebo for controlling pain, edema, and trismus following orthognathic surgeries.  Two reviewers extracted the data and evaluated the individual risk of bias of the eligible studies using the Cochrane Collaboration Risk of Bias Tool (RoB, version 2.0).  The initial search resulted in 808 articles, from which only 5 (a total of 190 subjects) were included in the qualitative synthesis.  The studies were published from 2014 to 2020.  Two presented a low-risk of bias + in the mean mouth opening of all patients subjected to bi-maxillary surgery who received LLLT.  However, the other study found a significant difference in maximum mouth opening (MMO) in the LLLT group at 14, 30, and 60 days following surgery.  The authors concluded that based on limited evidence, LLLT was presented as an auxiliary tool for reducing pain and trismus following surgery; however, the reduction of edema is controversial due to the absence of measuring standardization.

Orthognathic Surgery for the Treatment for Temporomandibular Disorders

There is limited evidence of the effectiveness of orthognathic surgery on temporomandibular disorders.  Abrahamsson et al (2007) examined if orthognathic surgery does affect the prevalence of signs and symptoms of temporomandibular disorders (TMDs).  A literature survey in the PubMed and Cochrane Library electronic databases was performed and covered the period from January 1966 to April 2006.  The inclusion criteria were controlled, prospective or retrospective studies comparing TMDs before and after orthognathic surgery in patients with malocclusion.  There were no language restrictions, and 3 reviewers selected and extracted the data independently.  The quality of the retrieved articles was evaluated by 4 reviewers.  The search strategy resulted in 467 articles, of which 3 met the inclusion criteria.  Because of few studies with unambiguous results and heterogeneity in study design, the scientific evidence was insufficient to evaluate the effects that orthognathic surgery had on TMD.  Moreover, the studies had problems with inadequate selection description, confounding factors, and lack of method error analysis.  The authors concluded that to obtain reliable scientific evidence, additional well-controlled and well-designed studies are needed to determine how and if orthognathic surgery alters signs and symptoms of TMD.

Lindenmeyer et al (2010) performed a systematic review of the best available research literature investigating the relation of oral and maxillofacial surgical procedures to the onset or relief of chronic painful TMD.  A comprehensive review of the databases CINAHL, Cochrane Library, Embase, Medline, NHS Evidence--Oral Health, PsycINFO, Web of Knowledge, and MetaLib was undertaken by 2 authors up to June 2009 using search terms appropriate to establishing a relation between orofacial surgical procedures and TMD.  The search was restricted to English-language publications.  Of the 1,777 titles reviewed, 35 articles were critically appraised, but only 32 articles were considered eligible.  These were observational studies that fell into 2 groups; 9 were seeking to establish a surgical cause for TMD.  Of these, only 2 of a series of 3 claimed that there was a significant link, but this claim was based on weak data (health insurance records) and was abandoned in a subsequent report.  Twenty-three studies were seeking to achieve relief by orthognathic surgical intervention.  These were also negative overall, with 7 articles showing varying degrees of mostly non-significant improvement, whereas 16 showed no change or a worse outcome.  No published report on the putative effect of implant insertion was found.  The authors concluded that these apparently contradictory approaches underline a belief that oral surgical trauma or gross malocclusion has a causative role in the onset of TMD.  However, there was no overall evidence of a surgical causal etiology or orthognathic therapeutic value.  This review emphasized that it is in the patients' best interest to carry out prospective appropriately controlled randomized trials to clarify the situation.

In a Cochrane review, Luther et al (2010) examined the effectiveness of orthodontic intervention in reducing symptoms in patients with TMD (compared with any control group receiving no treatment, placebo treatment or reassurance) and investigated if active orthodontic intervention leads to TMD.  The Cochrane Oral Health Group's Trials Register, CENTRAL, MEDLINE and EMBASE were searched.  Hand-searching of orthodontic journals and other related journals was undertaken in keeping with the Cochrane Collaboration hand-searching program.  No language restrictions were applied.  Authors of any studies were identified, as were experts offering legal advice, and contacted to identify unpublished trials.  Most recent search was April 13, 2010.  All randomized controlled trials (RCTs) including quasi-randomized trials assessing orthodontic treatment for TMD were included.  Studies with adults aged equal to or above 18 years old with clinically diagnosed TMD were included.  There were no age restrictions for prevention trials provided the follow-up period extended into adulthood.  The inclusion criteria required reports to state their diagnostic criteria for TMD at the start of treatment and for participants to exhibit 2 or more of the signs and/or symptoms.  The treatment group included treatment with appliances that could induce stable orthodontic tooth movement.  Patients receiving splints for 8 to 12 weeks and studies involving surgical intervention (direct exploration/surgery of the joint and/or orthognathic surgery to correct an abnormality of the underlying skeletal pattern) were excluded.  The outcomes were: how well were the symptoms reduced, adverse effects on oral health and quality of life.  Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted in triplicate and independently by 3 review authors.  As no 2 studies compared the same treatment strategies (interventions) it was not possible to combine the results of any studies.  The searches identified 284 records from all databases.  Initial screening of the abstracts and titles by all review authors identified 55 articles that related to orthodontic treatment and TMD.  The full articles were then retrieved and of these articles only 4 demonstrated any data that might be of value with respect to TMD and orthodontics.  After further analysis of the full texts of the 4 studies identified, none of the retrieved studies met the inclusion criteria and all were excluded from this review.  The authors concluded that there are insufficient research data on which to base clinical practice on the relationship of active orthodontic intervention and TMD.  There is an urgent need for high quality RCTs  in this area of orthodontic practice.

Dolwick and Widmer (2018) stated that well-controlled clinical trials supporting orthognathic surgery as the primary management for TMDs are lacking.  Most published studies lack an adequate experimental design to minimize biases.  Studies that minimized some biases did support an overall reduction in the frequency of TMD signs and symptoms in some Class III and Class II patients who had orthognathic surgery.  However, Class II correction with counter-clockwise rotation of the mandible increased TMD.  The authors concluded that individual variability precluded the ability to predict TMD outcome after surgery.  They stated that irreversible therapies such as orthognathic surgery should not be primary treatments in the management or prevention of TMDs.

In a prospective, cohort study, Toh and Leung (2022) examined the difference in prevalence of TMD before and after orthognathic surgery (OGS), especially in patients with mandibular asymmetry.  This trial entailed patients undergoing corrective orthognathic surgery.  Pre-operative and post-operative (3 months, 6 months and 1 year) TMD assessment were carried out according to the Diagnostic Criteria for TMD (DC/TMD) protocol.  A total of 64 patients were included in the study.  Overall, there was a significant reduction of 26.5 % in TMD prevalence from 60.9 % pre-operatively to 34.4 % 1-year post-operatively (p = 0.003).  A total of 37.5 % of patients had their TMD condition treated, 50 % had no change in their symptoms, while 12.5 % experienced a worsening of their symptoms.  No significant difference in terms of change in TMJ status was observed among the different ramus procedures, the type and magnitude of mandibular movement, skeletal class, and presence of mandibular asymmetry.  The authors concluded that it appeared that corrective orthognathic surgery for dentofacial deformities might provide a secondary benefit of treating TMD.  However, surgeons have to be aware that a small percentage of patients might experience a deterioration of their TMD condition, and that those who were previously asymptomatic may develop TMD symptoms after surgery.

Minimally Invasive Orthognathic Surgery

AlAsseri and Swennen (2018) stated that minimally invasive techniques are currently applied in many oral and maxilla-facial surgical procedures, including orthognathic surgery.  These investigators carried out a systematic review on the application of potentially minimally invasive procedures in orthognathic surgery to provide a clear overview of the relevant published data.  Articles in English on minimally invasive orthognathic procedures, published in the scientific literature, were obtained from the PubMed, Embase, and Cochrane Library databases, and an additional manual search (revised December 31, 2016).  After screening the abstracts and applying the eligibility criteria, a total of 403 articles were identified.  All articles reporting the potential for minimally invasive orthognathic surgery were included (n = 44).  The full papers were evaluated in detail and categorized as articles on a minimally invasive surgical approach (n = 4), endoscopically assisted orthognathic procedures (n = 17), or the use of a piezoelectric device in orthognathic surgery (n = 25); 2 articles were each included in 2 categories.  Although a small incision and minimal dissection is the basic principle of a minimally invasive technique, most articles (90.9 %) reported the endoscope and piezoelectric instrument as important tools in minimally invasive orthognathic surgery.  The authors concluded that evidence from available studies suggested that patients undergoing minimally invasive orthognathic surgery had less morbidity and made a faster recovery.  Moreover, they stated that further research should aim to obtain higher levels of evidence.

Use of Kinesio Taping for the Reduction of Swelling in Patients after Orthognathic Surgery

Lietz-Kijak and colleagues (2018) noted that orthognathic surgery (OGS) is associated with extensive surgical intervention within the soft and hard tissues of the facial region of the skull leading to inflammatory reactions.  The presence of post-operative swelling indicates the accumulation of exudate or transudate; both these fluids occur in surgery.  Massive swelling is a significant problem, because the tension of tissues intensifies pain sensations.  In a pilot study, these researchers examined the effectiveness of the Kinesio taping (KT) in patients after OGS in the area of the facial skull in terms of eliminating post-operative swelling.  This trial was carried out in 16 patients who suffered from this complication after bilateral sagittal split osteotomy.  he swelling was shown to be reduced after KT; within the same study the differences were statistically significant between the left and right sides and for the same side (p < 0.05).  The application of the lymphatic KT led to the reduction of tension in the affected area and restoration of proper lymphatic circulation in the region covered by swelling.  This allowed for the improvement of the blood and lymph micro-circulation and activation of self-healing processes.  The authors concluded that the analysis of the impact of the practical use of the lymphatic KT on complications after OGS revealed that it had a beneficial effect on the reduction of swelling.  They stated that the use of the KT appeared promising because it is economical, non-traumatic, simple-to-perform, and rarely causes undesirable allergies.  Moreover, they stated that further research is needed to examine if KT can reduce or eliminate the need for additional drugs, such as steroids.

Computer-Aided Three-Dimensional Simulation and Navigation in Orthognathic Surgery (CASNOS)

Chang and colleagues (2020) measured the accuracy of simulation and prediction of their computer-aided three-dimensional simulation and navigation in orthognathic surgery (CASNOS) protocol in adult patients treated with 2-jaw orthognathic surgery.  Adult patients with skeletal Class III malocclusions requiring 2-jaw orthognathic surgery were enrolled in the study; 3D imaging data of 1-month pre-surgical (T1) and 6-month post-surgical (T2) CT were compared to assess accuracy of CASNOS planning.  The accuracy of CASNOS protocol was evaluated by calculating the differences in the positions of selected landmarks between simulated surgical and post-surgical 3D images parameters, including ANB (angle between point A and B at Nasion.  A positive value represents that the maxilla is positioned anteriorly relatively to the mandible, while a negative value indicates that the maxilla is positioned posteriorly relative to the mandible), A-Nv (distance from point A to Nv [vertical reference to FH [Frankfort horizontal] plane and passing through Nasion [N].  Points anterior to Nv are given a positive value, while posterior to Nv are assigned a negative value]), Pog-Nv (distance from Pog to Nv), and the positions of selected landmarks (ANS [anterior nasal spine], point A, point B, Pog [Pogonion]) changes in horizontal (x-axis) and vertical (y-axis) directions.  Overall geographical discrepancy of planning was assessed by super-imposing the color mapping of T1 and T2 imaging.  A total of 30 adult patients with a mean age of 20.6 ± 1.5 years (female/male = 18/12) were enrolled.  The geographical changes of overall super-imposition between the planned and post-surgical imaging was 0.60 ± 0.19 mm (range of 0.42 to 1.08 mm).  The discrepancies between simulated and post-surgical ANB, A-Nv, Pog-Nv were 1.16 ± 0.36°, 1.25 ± 0.33 mm, 1.19 ± 0.35 mm, respectively.  The deviations between simulated and post-surgical point A and point B positions were within 1 mm in horizontal and vertical directions.  The authors concluded that the application of the pre-designed bony guiding splints of CASNOS protocol could allow surgeons to treat patients with cranio-facial deformities precisely.  These researchers stated that CASNOS provided a novel approach for orthodontists and surgeons accurately remedying the patients with complex cranio-facial discrepancies.  Moreover, these researchers stated that further development is still needed to set up virtually fabricated guiding splints and fixation plates so that clinicians can apply the protocol more efficiently to achieve the desired goals. 

The authors stated that the limitation of the CASNOS protocol is the time-consuming nature of manual design and fabrication of the guiding splints.  Despite the time taken for this technique, its disadvantages are considered clinically acceptable compared to those of conventional methods.  Furthermore, the lack of rigidity of mini-plates made them prone to distortion during handling the fixation process.  While there were no reports of broken fixation plates in any of the patients in this study, the use of manually-fabricated navigation plates that is potentially prone to distortion may be problematic in the long-term basis.  These researchers also noted that to fully utilize the advantages of the CASNOS protocol, they plan to develop a 3D printing technology to virtually fabricate guiding splints and fixation plates without usage of stereolithographic models.  Such 3D printing technology would involve laser additive manufacturing, so that the design and fabrication can be executed through computerized programs.  It is designed to allow clinicians to efficiently achieve the pre-designed outcome with rigid navigation splints.

In a retrospective study, Tsai and associates (2019) examined the volume of blood loss and operative time associated with management of non-growing patients with cleft lip and palate (CLP) using bi-maxillary orthognathic surgery (OGS) designed by a 3D CASNOS system.  This study included 53 skeletal Class III non-growing patients with unilateral CLP who underwent bi-maxillary OGS using either the CASNOS protocol (n = 30) or the traditional 2D method (n = 23).  The skeletal parameters of jaw-bone components, the levels of hemoglobin (Hb) and hematocrit (Hct) were measured before and after surgery.  The estimated blood loss (EBL) and actual blood loss (ABL) were also calculated.  The 2 groups did not differ significantly with regard to the demographic parameters (age, gender, and body mass index [BMI]), the pre-operative skeletal parameters and surgical changes of jaw-bone components.  The mean ABL of the CASNOS group was significantly lower than that of the control group (915.6 ± 280.5 versus 1,204.9 ± 201.0 ml, p < 0.001), and the changes in Hb and Hct level also followed a similar pattern in both groups.  The mean operative time was significantly shorter in the CASNOS group compared with the control group (384.2 ± 48.5 versus 469.0 ± 94.9 mins, p < 0.001).  The authors concluded that the findings of this study demonstrated that the application of the 3D CASNOS approach in OGS for the management of complicated Class III non-growing patients with CLP significantly shortened the operative time and reduced ABL in comparison with the traditional 2D methods.  These researchers stated that the 3D CASNOS method which consisted of surgical navigation guides, pre-bent titanium miniplates, and final splint tended to reduce the surgical difficulties and allowed the surgeons to easily locate the desired jaw-bone position.  However, as it is still a relatively new technique, further investigations are needed to prove that this protocol can be used efficiently and effectively in the reconstruction of more complicated craniofacial deformities.

The authors stated that the main drawback of this study was that the sample size used was quite small (n = 30 in the CASNOS group), and this could be attributed to the strict selection criteria.  The modified Gross formula includes the change in ongoing hemodilution that occurred during surgery, assuming maintenance of normovolemia.  Thus, individuals who underwent transfusion were excluded from this study, and this restricted the sample size considerably.  These investigators stated that future studies incorporating larger sample sizes are needed.  However, the authors believed that the present study should be considered as a pilot study examining the feasibility of using the CASNOS approach for bi-maxillary OGS.

Customized Titanium Plates

In a systematic review, Figueiredo and colleagues (2021) examined the accuracy of customized titanium plates in orthognathic surgery compared to standard outcome in virtual surgical planning; preferred reporting items for systematic reviews and meta-analysis (PRISMA) and Joanna Briggs Institute (JBI) guidelines were followed.  Research protocol was registered in PROSPERO.  A total of 6 data-bases and 2 gray literature repositories were used as sources of research articles.  Descriptive clinical studies, which performed orthognathic surgery using custom titanium plates, were included.  Risk of bias was assessed by "The Joanna-Briggs Institute Critical Appraisal tools for use in Systematic Reviews Checklist for Case Series".  Of the 11,916 studies initially identified, 7 met the eligibility criteria and were included.  The studies were published between 2015 and 2019.  The majority of the studies (57 %) had a low risk of bias, while 1 had a high risk of bias.  Total sample included 74 patients with 63 bi-maxillary surgeries and 11 uni-maxillary surgeries.  All studies showed acceptable accuracy within previously established clinical parameters.  The authors concluded that although the eligible articles evaluated the accuracy of the orthognathic surgery with respect to virtual planning, the wide variability of evaluation methodologies made it impossible to calculate a combined accuracy measure.  It was not possible to carry out a meta-analysis, so a pragmatic recommendation on the use of these plates is not possible.

Throat Packs in the Prevention of Post-Operative Nausea and Vomiting During Orthognathic Surgery

Faro and colleagues (2021) noted that the use of throat packs is common in maxillofacial surgeries.  However, the evidence to support the benefits of their use is controversial.  In a prospective, randomized, double-blind study, these investigators examined the effectiveness of throat packs in preventing post-operative nausea and vomiting, and their influence on the incidence of sore throat and dysphagia in patients undergoing orthognathic surgery.  This trial included 54 patients who were randomized to 2 groups: with throat pack (n = 27) and without throat pack (n = 27).  A total of 50 patients (25 in each group) were included in the analysis; 66 % women and 34 % men, mean age 29.44 ± 8.53 years.  Post-operative nausea and vomiting (Kortilla scale), sore throat (visual analog scale [VAS]), and dysphagia were evaluated.  Statistically significant differences in favor of the without-pack group were found for the variables throat pain at 24 hours (p = 0.002) and dysphagia at 2 hours (p = 0.007) and 24 hours (p < 0.001).  There was no difference between the groups regarding post-operative nausea and vomiting (p = 1.00).  The authors concluded that the findings of this study indicated that throat packs as utilized here did not prevent post-operative nausea and vomiting and were associated with worse sore throats and post-operative dysphagia.

Biodegradable Osteosyntheses in Orthognathic Surgery

Gareb and colleagues (2021) stated that titanium osteosynthesis is currently the gold standard in orthognathic surgery.  Use of biodegradable osteosyntheses avoids removal of plates/screws in a 2nd operation.  In a systematic review, these researchers examined the effectiveness and morbidity of biodegradable versus titanium osteosyntheses in orthognathic surgery.  Patients with syndromic disorder(s) and/or cleft lip/palate were excluded.  Randomized, prospective and retrospective controlled studies were searched for in 9 databases (February 2021).  The time periods peri-operative, short-term, intermediate, long-term, and overall follow-up were studied.  Meta-analyses were carried out using random-effects models.  A total of 9,073 records was assessed, of which 33 were included, comprising 2,551 patients.  A total of 7 RCTs had “some concerns”; while another 7 RCTs had “high” risk of bias (Cochrane-RoB2).  No differences in malunion (qualitative analyses), mobility of bone segments [RR 1.37 (0.47; 3.99)], and malocclusion [RR 0.93 (0.39; 2.26)] were found.  The operative time was longer in the biodegradable group [SMD 0.50 (0.09; 0.91)].  Symptomatic plate/screw removal was comparable among both groups [RR 1.29 (0.68; 2.44)].  Skeletal stability was similar in most types of surgery.  The authors concluded that biodegradable osteosyntheses is a valid alternative to titanium osteosyntheses for orthognathic surgery, but with longer operation times.  Moreover, these researchers stated that since the quality of evidence varied from very low to moderate, high-quality research is needed to determine the potential of biodegradable osteosyntheses.  These researchers stated that future studies should also include cost‐effectiveness as the outcome measure, including primary (i.e., peri-operative) and secondary costs (e.g., additional interventions, travelling expenses, absence of work).  Finally, RCTs should adhere to the Consolidated Standards of Reporting Trials (CONSORT) guidelines to assure high‐quality reporting, minimize reporting bias, and enable assessment and pooling of future data.

The authors stated that this study had several drawbacks.  First, the fact that blinding (i.e., by surgeons and the outcome assessment) was not possible owing to the properties of titanium and biodegradable osteosynthesis systems.  However, the main reasons for increasing the risk of bias were bias due to deviations from the intended intervention as well as bias due to missing outcome data.  This emphasized the need of pre‐specified, pre‐registered, and well‐defined protocols of future RCTs.  In particular, these protocols should focus on well‐defined inclusion and exclusion criteria (e.g., separating the inclusion of maxillary and mandibular osteotomies) and endpoints to minimize reporting bias.  Furthermore, appropriate follow‐up is advocated to minimize attrition bias (e.g., greater than 1 year follow‐up for symptomatic device removal and skeletal stability); and indications for device removal should be clearly defined and followed to reduce detection bias.  Second, since data regarding 3D analysis of patients undergoing orthognathic surgery is growing, they could and should be used in the analyses of skeletal stability.  Third, as the patient's opinion regarding outcomes is of high importance, patient reported outcomes (e.g., mandibular function impairment questionnaire [MFIQ], subjective malocclusion) should be assessed.  Moreover, reporting of patient and surgical characteristics, and outcomes, including details regarding the usage of alcohol and tobacco, the used osteosynthesis systems with compositions and sizes, and the maxilla-mandibular fixation, orthodontic treatment, and post-operative dietary policies, should be improved.

Peri-Operative Therapies for the Management of Post-Operative Edema Following Orthognathic Surgery

In a systematic review and meta-analysis, Galdino-Santos et al (2023) examined the effectiveness of peri-operative systemic and non-systemic therapies in reducing edema following orthognathic surgery.  A total of 4 databases (PubMed, Web of Science, Bireme, and Scopus) were searched.  Only randomized clinical trials were included and evaluated using the RoB 2.0 software (Cochrane Collaboration, London, UK).  Studies were grouped into time of assessment and systemic/non-systemic therapy.  A total of 18 studies were included in this review (8 in the meta-analysis, n = 349).  The qualitative assessment of systemic (enzyme therapy, dexamethasone, betamethasone, and Venoplant) and non-systemic therapies (thermotherapy and K-Taping) appeared to reduce edema.  Manual lymphatic drainage (MLD) after 72 hours (CI: -1.03 to 2.31; p = 0.45), and 30 days (CI: -1.53 to 0.49; p = 0.49), and laser after 24 hours (CI: -1.36 to 1.48; p = 0.93), 72 hours (CI: -4.81 to 2.92; p = 0.63), 30 days (CI: -3.44 to 0.99; p = 0.28), and 90 days (CI: -1.83 to 0.96; p = 0.54) showed no significance.  Thermotherapy reduced edema after 48 hours (CI: -48.47 to -13.31; p = 0.0006) and 30 days (CI: -14.73 to -1.98; p = 0.01).  The authors concluded that the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) tool showed moderate evidence for thermotherapy (significant reduction of edema), whereas the MLD and laser results were rated as high certainty of evidence (no reduction of edema).

Outpatient Orthognathic Surgery

Prevost et al (2023) noted that transitioning from non-outpatient orthognathic surgery to outpatient surgery is a new challenge, and it is essential to target the eligible population as precisely as possible.  Several researchers described series of outpatient orthognathic surgery but did not include the reasons for their success or failure.  In a prospective, cohort study, these investigators identified the factors significantly associated with "successful" outpatient orthognathic treatment.  The secondary objective was to determine the factors significantly associated with prolonged hospital stays (2 or more nights).  This trial included patients undergoing orthognathic surgery and was carried out over a period of 1 year.  These researchers recorded the prognostic factors that contributed to successful outpatient treatment and prolonged hospital stays.  These factors were evaluated by bi-variate and multi-variate analysis.  A total of 102 patients were included, and the success rate of treatment was 65 %.  The variables that were isolated by multi-variate analysis were: patients over the age of 22, procedures ending before 1 pm, brief operations, the absence of both post-operative vomiting, and the administration of morphine.  The authors concluded that patient selection, organization of outpatient facilities, as well as anesthetic protocols contributed to the success of outpatient orthognathic surgery.  These initial considerations provided a framework for their practice; however, the considerations that predicted the failure of outpatient surgery will need to be clarified.

Patient-Specific Osteosynthesis is for Orthognathic Surgery

In a systematic review and meta-analysis, Diaconu et al (2023) examined the accuracy/stability of patient-specific osteosynthesis (PSI) in orthognathic surgery according to three-dimensional (3D) outcome analysis; and comparison to conventional osteosynthesis and computer-aided designed and manufactured (CAD/CAM) splints or wafers.  The PRISMA guidelines were followed; and 6 academic databases and Google Scholar were searched.  Records reporting 3D accuracy/stability measurements of bony segments fixated with PSI were included.  Of 485 initial records, 21 met the eligibility (566 subjects), 9 of which also qualified for a meta-analysis (164 subjects).  A total of 6 studies had a high risk of bias (29 %), and the rest were of low or moderate risk.  Procedures comprised either single-piece or segmental Le Fort I and/or mandibular osteotomy and/or genioplasty.  A stratified meta-analysis including 115 subjects with single-piece Le Fort I PSI showed that the largest absolute mean deviations were 0.5 mm antero-posteriorly and 0.65° in pitch.  PSIs were up to 0.85 mm and 2.35° more accurate than conventional osteosynthesis with CAD/CAM splint or wafer (p < 0.0001).  However, the clinical relevance of the improved accuracy has not been shown.  The authors concluded that the available evidence on PSI for multi-piece Le Fort I, mandibular osteotomies and genioplasty procedure is characterized by high methodological heterogeneity and a lack of RCTs.  The literature is lacking on the 3D stability of bony segments fixated with PSI.  Moreover, these researchers stated that further investigation is needed on the stability of PSI use in orthognathic surgery.  Regarding the issue of the standardization of accuracy measurements in orthognathic surgery, the literature appeared to move towards the full 3D measurement of translation and rotation.  However, heterogeneity persists in methodologies with respect to the points/landmarks at which measurements are performed.  These investigators stated that future research is needed to focus on PSI accuracy in orthognathic surgery, in regard to multi-piece Le Fort I procedures, mandibular osteotomies, genioplasty and long-term stability measurements, with a prospective study design and control groups.  To ensure high-quality results and comparability, future investigators are also encouraged to focus on automatic 3D analysis according to standardized methods.

The authors stated that this meta-analysis had several drawbacks.  First, within the included records, translational error measurements were performed at the upper incisors, at the geometrical center of the bone segment, or were derived from a rigid transformation matrix of the bone segment.  These records have been pooled together for the analysis while acknowledging the potential weakness of not using the same exact anatomical landmarks.  It is considered less informative to have further stratified the analysis based on this difference in the specificity of the measurement point, as the analysis of such reduced groups would prevent any meaningful conclusions from being drawn.  Second, some of the mean values required in the analysis were estimated from the available median values and inter-quartile range (IQR) values.  Third, the stratum of the meta-analysis with controlled studies contained only 5 records, and it was further stratified by 1 of the studies reporting an unusually narrow standard deviation.

Glossary of Terms

Table: Glossary of Terms
Term Definition
Genial osteotomies / ostectomies Chin surgeries


The above policy is based on the following references:

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