pediatric/craniofacial · compensated by orthodontics. orthodontic tooth movements to obtain...

PEDIATRIC/CRANIOFACIAL

Alloplastic Augmentation of the FacialSkeleton: An Occasional Adjunct or Alternativeto Orthognathic SurgeryMichael J. Yaremchuk, M.D.

Gabe Doumit, M.D.Matthew A. Thomas, M.D.

Boston, Mass.

Background: Alloplastic implants can be adjunctive to orthognathic surgery bycorrecting contour irregularities or disharmonies after skeletal movements.Implant augmentation can also simulate the visual effect of osteotomies inpatients with skeletal deficiencies whose occlusion is normal or has been cor-rected. Although sometimes it is an adjunct or an alternative to facial skeletalrearrangements, facial skeleton augmentation is not a substitute for orthog-nathic surgery.Methods: Alloplastic implants designed specifically to augment the infraorbitalrim can correct the residual upper midface deficiency remaining after Le FortI maxillary advancement. When used with paranasal and malar implants, theycan simulate the visual effect of the Le Fort III osteotomy with advancement.Paranasal implants can simulate the appearance after Le Fort I advancement.Mandible and extended chin implants can correct skeletal irregularities anddeficiencies after sagittal and horizontal osteotomies. They can also simulate thevisual effect of these osteotomies.Results: The application of these concepts has been effective, with low mor-bidity, in 294 patients. No implants extruded or migrated. Eight patients (3percent) had early postoperative infections. There were no late infections.Ten of 108 patients (9 percent) with midface implants had implant visibilitywith time.Conclusion: Alloplastic augmentation of the facial skeleton can be a usefuladjunct or an alternative to orthognathic surgical procedures in situationswhen the occlusion is normal or has been corrected. (Plast. Reconstr. Surg.127: 2021, 2011.)

Facial skeletal disharmony most often mani-fests as midface or mandibular deficiencies.When severe, these deficiencies result in mal-

occlusion and are treated with skeletal osteotomyand rearrangement. Patients with less severe skel-etal deficiencies and occlusal abnormality canhave their occlusal relationships improved withorthodontic tooth movement alone. In both pa-tient groups, these treatments may optimize oc-clusion and, thus, dental function. However, the

resulting skeletal contours are often less thanideal. Both treatment groups may benefit fromselective augmentation of their facial skeletonwith alloplastic implants to normalize skeletal con-tours and thus improve facial appearance.1–5 Al-though useful for patients with certain skeletaldisharmonies, facial skeletal augmentation is nota substitute for orthognathic surgery.

This article describes the use of alloplastic im-plants as an occasional adjunct or alternative toorthognathic surgery. It integrates patient exam-ples in the description and application of the con-cept. It documents the clinical experience of theapplication of these concepts.

From Massachusetts General Hospital.Received for publication August 9, 2010; accepted October4, 2010.Presented in part at Current Perspectives in OrthognathicSurgery: Point-Counterpoint by the Experts, in Washington,D.C., May of 2006, and at the 87th Annual Meeting of theAmerican Association of Plastic Surgeons, in Boston, Mas-sachusetts, April 5 through 8, 2008.Copyright ©2011 by the American Society of Plastic Surgeons

DOI: 10.1097/PRS.0b013e31820e9263

Disclosure: The authors have no financial interestto declare in relation to the content of this article. Nooutside funding was received for this work.

www.PRSJournal.com 2021

PATIENTS AND METHODS

Orthognathic Surgery AdjunctAfter Le Fort I AdvancementMidface deficiency associated with significant

malocclusion is most often treated with horizontalosteotomy of the maxilla at the Le Fort I level withadvancement of the tooth-bearing segment. Thestandard Le Fort I osteotomy advances only themaxillary alveolus and adjacent skeleton beneaththe infraorbital foramen. It does not include theinfraorbital rim and malar areas. Patients in whomthe infraorbital region was deficient before LeFort I osteotomy will continue to be deficient post-operatively. The rim deficiency in the parasagittalplane may be accentuated by the more advancedposition of the tooth-bearing segment. Cephalomet-ric analysis in preparation for maxillary advance-ment focuses on the midsagittal plane. Rosen, a vi-sionary in optimizing the aesthetic consequences oforthognathic procedures, argued that considerationof the parasagittal plane can be equally or perhapsmore important for facial aesthetics.6

The postoperative imbalance in midface para-sagittal projection may be corrected by alloplasticaugmentation of the skeleton above the advancedtooth-bearing segment. This augmentation alwaysincludes the infraorbital rim7 and is often used incombination with malar implants (Fig. 1).

After Mandibular OsteotomiesPatients with class II dental malocclusion

caused by mandibular deficiency are usuallytreated by sagittal split osteotomy. This procedureseparates the tooth-bearing symphysis and adja-cent bodies from the rami. Requisites for posi-tioning the resultant anterior and posterior seg-ments to improve occlusion, allow bone healing,and maintain joint function may result in displeas-ing postoperative contours and disharmonies.The anterior repositioning of the tooth-bearingsegment is dictated by occlusal relations. Its sep-aration from the posterior segment creates an ir-regularity at the site of the osteotomy. This area ofnarrowing along the inferior border of the man-dible may be visible in certain individuals.

Positioning of the posterior segment requiresthat its condyle be seated in the glenoid fossa andthat there be sufficient contact at the osteotomysite with the occlusal segment to allow bone heal-ing. Thus, the position of the mandibular angle isdictated by the fulfillment of these criteria. Becausethe position and obliquity of the bilateral osteoto-mies are never identical, the position of the mandi-ble angles is destined to some degree of asymmetryand unpredictability. This may result in an aesthet-

ically displeasing position of the ramus, resulting inan angle with insufficient height, insufficient width,or asymmetry. Postoperative bone resorption mayalso contribute to posterior deficiency.

Horizontal osteotomy of the chin with ad-vancement of the inferior segment (sliding genio-plasty) is often performed in conjunction with thesagittal split osteotomies. Unless the horizontalosteotomy is carried well posterior to the mentalforamen, a contour irregularity at the site of theosteotomy may be visible. The notching or inden-tation is especially detrimental to those who havea preexisting prejowl sulcus.

Alloplastic implants are available to camou-flage contour irregularities and asymmetries thatoccur after mandibular osteotomies. Alloplasticaugmentation of the posterior mandible may in-crease posterior width, increase ramus height, de-crease inclination of the mandibular border, andcorrect inferior border irregularities at the sagittalosteotomy sites. Extended chin implants can beused to correct indentations and lessen asymme-tries after horizontal osteotomies (Fig. 1).

Fig. 1. Artist’s rendition of adjunctive use of alloplastic implantsto correct skeletal imbalances and irregularities after orthog-nathic procedures. An implant designed to augment the infraor-bital rim and anterior malar area corrects the upper midface de-ficiency after Le Fort I osteotomy and advancement. An implantplaced in the posterior mandible smooths the area of narrowingalong the inferior border at the sagittal osteotomy site and re-stores angle projection and ramus height. The extended chin im-plant, in this case, corrects the step deformity after horizontalosteotomy and adds chin projection.

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Orthognathic Surgery AlternativeMidface and mandibular hypoplasia are com-

mon facial skeletal variants. In patients with thesemorphologies, occlusion can be normal or can becompensated by orthodontics. Orthodontic toothmovements to obtain occlusion have been re-ported to be applicable for correction of up to 8mm for positive overjet, 4 mm for negative overjet,and 3 mm for transverse width discrepancy.8 Inskeletally deficient patients whose occlusion isnormal or has been previously normalized by or-thodontics, skeletal repositioning would necessitateadditional orthodontic tooth movement. Such atreatment plan is time consuming and costly. It in-troduces many morbidities associated with skeletalosteotomies including the contour irregularitiesnoted above, possible relapse, and sensory nerveinjury.9 It is therefore appealing to few patients. Inthese patients, the appearance of skeletal osteoto-mies and rearrangements can be simulated throughthe use of facial implants.10 Diagrammatic represen-tations of how implant surgery can mimic the ap-pearance of skeletal osteotomies in patients with nor-mal or corrected occlusion are shown in Figures 2through 4. Augmentation of the pyriform aperturearea can simulate the visual effect of Le Fort I os-teotomy with advancement3 (Fig. 2). The use of mul-tiple midface implants including those that augment

the infraorbital rim and the malar and pyriformareas can simulate the visual appearance of Le FortIII osteotomy and advancement2(Fig. 3). Combina-tions of mandible and chin implants can simulatethe appearance of sagittal and horizontal osteoto-mies with advancement11 (Fig. 4).

Preoperative EvaluationBecause occlusion is satisfactory or has been cor-

rected in these patient groups, skeletal augmenta-tion is determined by the aesthetic concerns of thepatient. Physical examinations together with stan-dardized photographs are paramount in analysisand surgical planning. Plain radiographs and, par-ticularly, computed tomographic scans with three-dimensional reconstruction can be useful adjuncts.In certain instances, particularly those patients withsignificant asymmetries, models obtained from com-puted tomographic data add the physical dimensionto the planning and have been used to manufacturecustomized implants.

Overview of Operative TechniqueA general anesthetic is preferred. This ap-

proach protects the airway during the operationand allows optimal intraoral preparation and sur-gical access to the midface and mandible. To op-

Fig. 2. Diagrams show how implant augmentation of the lower midface (pyriform aperture) cansimulate the visual appearance of Le Fort I osteotomy and advancement without altering dentalocclusion. (Left) Illustration of lower midface concavity with class III malocclusion corrected by LeFort I osteotomy with advancement. (Right) Lower midface implants provide the visual effect of LeFort I osteotomy and advancement but do not alter occlusion.

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Fig. 4. Diagrams showing how implant augmentation of the mandible can simulate the visualappearance of sagittal and horizontal osteotomies of the mandible without altering dental occlu-sion. (Left) Mandibular deficiency with class II occlusion corrected by sagittal and horizontal osteot-omies of the mandible. Note that the occlusion has been corrected from class II to class I. (Right) Inthe patient with mandibular deficiency and class I occlusion, the visual effect of sagittal and hori-zontal osteotomies with advancement has been simulated with mandible and chin implants. Notethat the class I occlusion is unchanged. Notice also that the border regularities inherent in skeletalosteotomies are avoided when implants are used.

Fig. 3. Diagrams showing how multiple implant augmentation of the upper and lower midfaceskeleton can simulate the visual appearance of Le Fort III osteotomy and advancement withoutaltering dental occlusion. (Left) Illustration of midface concavity and class III malocclusion correctedby Le Fort III osteotomy with advancement. (Right) Multiple midface implants provide the visualeffect of Le Fort III osteotomy and advancement but do not alter occlusion.


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Fig. 5. A 35-year-old woman had undergone Le Fort I maxillary advancement and sagittal and hori-zontal mandibular osteotomies. Infraorbital rim augmentation and subperiosteal midface elevationwas performed to improve midface aesthetics. Infraorbital rim augmentation and midface resuspen-sion has elevated the cheek prominence, resulting in an improved lid cheek interface, with resultantshort lid and full cheek. Mandible implants were placed to increase posterior width and increase angledefinition. An extended chin implant improved the anterior border contour. (Above) Preoperative andpostoperative frontal views. (Center) Preoperative and postoperative lateral views. (Below) The artisthas drawn the underlying skeleton and implant applications.


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timize hemostasis, a dilute epinephrine solution isinfiltrated in the operative site.

Intraoral sulcus incisions are used to access themidface for placement of paranasal and malarimplants. Infraorbital rim augmentation requiresperiorbital (lower blepharoplasty) incisions. Theposterior mandible is accessed through intraoralsulcus incisions, and it is the authors’ preferenceto access the chin from a submental approach.

The area to be augmented is widely exposed inthe subperiosteal plane. Implants are modified asnecessary to meet the specific needs of the patient.It is the author’s preference to use porous poly-ethylene implants fixed with titanium screws.Screw fixation prevents implant movement, allowsthe implant to be contoured in place, and oblit-erates gaps between the posterior surface of theimplant and the anterior surface of the skeleton.Gaps result in unanticipated increases in implantprojection and thus skeletal contour.1–3,7,11

Suction drains are routinely used. Chlorhexi-dine gluconate mouthwashes are prescribed foruse 3 days postoperatively. Intravenous antibioticsare administered perioperatively. Oral antibioticsare prescribed for 1 week after surgery.

RESULTSThis concept has been used in 294 patients (203

female patients and 91 male patients) over an 8-yearperiod. The average age was 34 years (range, 17 to68 years). Sixty had implant surgery as an adjunct topreviously performed orthognathic surgery, and 234patients had implant surgery as an alternative toorthognathic surgery. No implants extruded or mi-grated. Ten of 108 patients (9 percent) with midfaceimplants had visibility with time, reflecting the factthat soft tissues change over time whereas implantsdo not lose their projection.

Eight patients (3 percent) had postoperative in-fections. Two of these eight patients had a history ofprevious implant-related infections treated unsuc-cessfully with months-long courses of antibiotics.One of these patients was human immunodeficiencyvirus–positive. Another patient had previously un-dergone radical neck dissection and radiation ther-apy. Three patients presenting with infection duringthe first postoperative week were treated successfullywith repeated irrigations and intravenous antibiot-ics. The other four patients presented 3 to 4 weeksafter surgery and were treated with implant re-moval. One of the patients (human immunodefi-ciency virus–positive) successfully treated withinthe first week presented 2 years after surgery withan orbital cellulitis. His implant was removed to

eliminate it as a possible septic focus. No puru-lence was found and results of wound cultureswere negative for bacterial growth.

Fig. 6. A 26-year-old woman had undergone sagittal split and hor-izontal osteotomies of the mandible to correct mandibular defi-ciency with class II malocclusion. Contour deficiencies and irregu-larities, including deficient gonial angles, were improved withmandible and chin implants. The vertical height of the chin was re-duced by contouring at its inferior border. (Above and center) Pre-operative and postoperative (1 year) oblique views. (Below) The art-ist has drawn the underlying skeleton and implant applications.


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No other patient presented with a late infec-tion that could be related to the implant. Patientswho have had implant surgery as an adjunct oralternative to orthognathic surgery are presentedin Figures 5 through 9.

DISCUSSIONRosen, in multiple writings,6,12–14 was one of the

first to point out aesthetic inadequacies that mayaccompany adherence to classic skeletal movementsbased on cephalometric data. He emphasized thatwhen given alternatives to satisfy occlusal inadequa-

cies, it is usually better to expand rather than toreduce the facial skeleton. This skeletal expansionprovides support for, and allows better drape of, thesoft-tissue mask with, as he demonstrated, a moreyouthful and attractive appearance. The use of al-loplastic implants as an adjunct to previously per-formed orthognathic procedures or as a simulationof skeletal advancements in patients with normal ororthodontically corrected occlusion inevitably ex-pands the skeleton. As advocated by Rosen, it addsto midface convexity or mandibular border and an-gle definition with their attendant aesthetic benefits.

Fig. 7. A 22-year-old woman with lower midface deficiency and normal occlusion underwent para-nasal augmentation at the time of aesthetic rhinoplasty. Note the increase in lower midface projec-tion simulating the appearance of Le Fort I osteotomy with advancement. (Above) Preoperativeand postoperative (1 year) lateral views. (Below) The artist has drawn the underlying skeleton andimplant applications.


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Contour irregularities and deficiencies after or-thognathic procedures in the midface have beennoted and addressed by others.4,15 This has largelybeen confined to the midface after Le Fort osteot-omy. Nocini et al. have designed a midfacial zonalanalysis to identify and address deficiencies in themidface with implants at the time of jaw surgery.5

Malar deficiency has been most often ad-dressed with implants at the time of orthognathicsurgery or during a second procedure. It is theauthor’s contention that malar augmentationalone as an adjunct may introduce yet anotherimbalance. Malar augmentation usually widens

the midface, which tends to exaggerate the uppermidface concavity. Thus, infraorbital rim augmen-tation is considered the critical element in creat-ing midface balance after Le Fort I advancement.More lateral malar augmentation may be an ap-propriate adjunct.

When augmenting both the upper and loweraspects of the midfacial skeleton to simulate a LeFort III advancement, multiple implants ratherthan a single large implant are preferred. A singlelarge midface implant is unlikely to adapt to theunderlying curvatures of the native skeleton.Large gaps between the posterior surface of the

Fig. 8. A 32-year-old man with midface deficiency and corrected occlusion underwent midfaceaugmentation with infraorbital rim, paranasal, and malar implants. (Above) Preoperative andpostoperative (1 year) lateral views. (Below) The artist has drawn the underlying skeleton andimplant applications.


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implant and the anterior surface of the skeletonresult. These gaps result in unanticipated increasesin implant projection (implant thickness � gap �effective implant projection). The facial contourslose their innate shape and take on an “implantface” appearance.

Both the soft tissues and the skeleton contrib-ute to midface contour and convexity. Thus, bothsoft-tissue and skeletal augmentation can be ap-propriate for creating midface convexity. How-ever, these modalities are not equivalent in theirimpact on the appearance of the midface. Free fatgrafting and the injection of various fillers is in-tuitive and appropriate for the restoration of soft-

tissue volume loss caused by senile atrophy. It hasa limited role in simulating the effect of an in-crease in skeletal projection. Whereas augmentingthe facial skeleton results in an increase in theprojection of the skeleton, augmenting the soft-tissue volume results in an inflation of the soft-tissue envelope and blunting of the contours ofthe skeleton. Overaugmentation of either compo-nent brings home the point. If overly large im-plants were placed on the skeleton, the appear-ance would be too defined and, ultimately,skeletal. If too much fat or filler were placed in thesoft-tissue envelope, an increasingly spherical andotherwise undefined shape would result. A similar

Fig. 9. A 32-year-old woman with mandibular deficiency and corrected occlusion underwent chin andmandible implant augmentation. (Above) Preoperative and postoperative (2 years) oblique views.(Below) The artist has drawn the underlying skeleton and implant applications.


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situation arises when soft-tissue augmentation isperformed to simulate the appearance of signifi-cant chin or mandible augmentation.

Soft-tissue volume augmentation has beencomplementary16,17 to both the adjunctive and al-ternative use of alloplastic implants to orthog-nathic procedures. Because soft tissues changeover time and implants do not, soft-tissue aug-mentation can mask implant visibility in patientswith senescence-attenuated soft-tissue envelopes.When patients are both skeletal and soft-tissuedeficient, the use of both modalities can optimizethe result.

CONCLUSIONSAlloplastic augmentation of the facial skeleton

can be a useful adjunct or an alternative to or-thognathic surgical procedures in situations whenthe occlusion is normal or has been corrected.Alloplastic implants can improve contour irregu-larities left after skeletal movements. In patientswith acceptable occlusion, their use can simulatethe visual effect of skeletal movements.

Michael J. Yaremchuk, M.D.Massachusetts General Hospital

Boston, Mass. [email protected]

PATIENT CONSENTPatients provided written consent for the use of their

images.

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Aesthet Surg J. 2007;27:539–550.2. Yaremchuk MJ. Making concave faces convex. Aesthetic Plast

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3. Yaremchuk MJ, Israeli D. Paranasal implants for correctionof midface concavity. Plast Reconstr Surg. 1998;102:1676–1684; discussion 1685.

4. Robiony M, Costa F, Demitri V, Politi M. Simultaneous ma-laroplasty with porous polyethylene implants and orthog-nathic surgery for correction of malar deficiency. J Oral Max-illofac Surg. 1998;56:734–741; discussion 742.

5. Nocini PF, Boccieri A, Bertossi D. Gridplan midfacial analysisfor alloplastic implants at the time of jaw surgery. Plast Re-constr Surg. 2009;123:670–679.

6. Rosen HM. Aesthetic Perspectives in Jaw Surgery. New York:Springer; 1999.

7. Yaremchuk MJ. Infraorbital rim augmentation. Plast ReconstrSurg. 2001;107:1585–1592; discussion 1593–1595.

8. Squire D, Best AM, Lindauer SJ, Laskin DM. Determining thelimits of orthodontic treatment of overbite, overjet, andtransverse discrepancy: A pilot study. Am J Orthod DentofacialOrthop. 2006;129:804–808.

9. Morris DE, Lo LJ, Margulis A. Pitfalls in orthognathic sur-gery: Avoidance and management of complications. ClinPlast Surg. 2007;34:e17–e29.

10. Yaremchuk MJ. Indications, evaluation and planning. In:Yaremchuk MJ. Atlas of Facial Implants. Philadelphia: Saun-ders-Elsevier; 2007:3–22.

11. Yaremchuk MJ. Mandibular augmentation. Plast ReconstrSurg. 2000;106:697–706.

12. Rosen HM. Occlusal plane rotation: Aesthetic enhancementin mandibular micrognathia. Plast Reconstr Surg. 1993;91:1231–1240; discussion 1241–1244.

13. Rosen HM. Facial skeletal expansion: Treatment strategiesand rationale. Plast Reconstr Surg. 1992;89:798–808.

14. Selber JC, Rosen HM. Aesthetics of facial skeletal surgery.Clin Plast Surg. 2007;34:437–445.

15. Carboni A, Cerulli G, Perugini M, Renzi G, Becelli R. Long-term follow-up of 105 porous polyethylene implants used tocorrect facial deformity. Eur J Plast Surg. 2002;25:310–314.

16. Reiche-Fischel O, Wolford LM, Pitta M. Facial contourreconstruction using an autologous free fat graft: A casereport with 18-year follow-up. J Oral Maxillofac Surg. 2000;58:103–106.

17. Ellenbogen R, Motykie G, Youn A, Svehlak S, Yamini D. Facialreshaping using less invasive methods. Aesthet Surg J. 2005;25:144–152.


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