Analyses of malar projection
Changes in the esthetic appearance of the face is highly depended on the bony structures of the facial skeleton, including the malar-midface region, nose, and chin. Alterations of soft tissue and skin alone will not satisfy all of our aesthetic demands. Multiple factors such as skin (texture, color, thickness and...), soft tissue (symmetry, composition, location and...) and facial bony contours (size, shape, location, symmetry and...) contributes to creating esthetically appealing appearance of the face.
Since many years ago numerous surgical and office based techniques have been introduce to augment, reduce or refine the most projected points of the face such as cheek, chin, nose, Para-nasal area, angle of the jaw..According to the literature the techniques can be classified to: 1) Office based or non-invasive techniques; such as fillers injection, facial lipostructure or facial liposuction which modified the soft tissue coverage of the facial skeleton.2) Facial prosthesis. 3) Maxillofacial osteotomies. Based on our knowledge the first and second group have been considered more in the literatures and text book of the Oral and Maxillofacial Surgery (OMFS) or Plastic Surgery, it is perhaps related to the more complications of the osteotomy techniques or easiness of the office –based one. OMFS are familiar with orthognatic surgeries and their skill in this field can help them to plan the third one,especially in cases whom the long term results should be considered. In current chapter we reviewed the esthetic osteotomy techniques of the facial skeleton and introduce a surgical techniques for management of the most projected points of the face namely:
Piriform augmentation osteotomies
Mandibular Angle modification
Angle augmentation osteotomies
Angle reduction oeteotomies
Malar augmentation osteotomies
Malar reduction osteotomies
Frontal Bossing reduction techniques
2. Chin modification
The creation or restoration of an esthetically pleasing facial contour can encompass many surgical approaches. Several surgical techniques are available for correcting and giving harmony to the lower third of the face. In this respect, some well-known techniques seek to correct the shape and size of the chin using different kinds of chin implants or osteotomies in an effort to move it and change its spatial location, thus determining a new facial contour.
2.1. Augmentation genioplasty
Genioplasty (anterior horizontal mandibular osteotomy) means a plastic procedure on the chin that involves both bony components (ie, anterior portion of the base of the mandible) and the soft tissue component.The procedure can be performed either alone or as an adjunct to other orthognathic and facial plastic surgeries. Either direct osteoplasty and soft tissue correction or implantation of an alloplastic material/cartilage/bone has been recommended for genioplasty. Since 1942, with first sliding advancement genioplasty that was described by Hofer, various genioplasty techniques with various indications, advantages, and disadvantages have been developed for correction of microgenia and macrogenia. In recent chapter we did not focused on augmentation genioplasty techniques.The readers can update their knowledge by reviewing the other chapters or books.
2.2. Reduction genioplasty
In the event of anterior mandibular bony excess different surgical approaches can be used. Each have their own limitations and disadvantages. For instance simple burring down removal of bony excess from anterior mandible through an intraoperative approach will usually result in an abnormal appearance and is not the best choice of treatment.
Reduction genioplasty surgical procedure results in narrowing or shortening of the chin. However, the literature lacks data about the best technique, indications, complications, and long-term results. The soft tissue envelope of the chin area usually follows the genial osseous movement approximately 90% or more, but the predictability ratio of horizontal reduction genioplasty is limited; it follows approximately 50% to 60%.
To date, only 2 articles have been published about the narrowing of the chin by use of this technique.Minor step-off at the chin-mandible junction and mild transient numbness of the lower lip, jowls, and bunching of the chin were reported as the most common complications of this technique. Because the lingual muscle is released, there is a risk of avascular necrosis of the distal segments, and the chin prominence should be minimally degloved to prevent this complication. Furthermore, because the mid-symphysis area is removed, the chance of asymmetry or unesthetic results could be increased(fig.1). another techniques such as horizontal T osteotomy were also described but is not used widely(fig.2).[10, 46]In 2013 we described[1, 47] a novel technique to reduce the prominent chin 3-dimentionally(fig.3).This new genioplasty (Zigzag genioplasty) makes it possible to decrease the vertical and transverse dimension of the chin alone or simultaneously, symmetrically or asymmetrically. This genioplasty alsomakesit possible to decrease the mental sagittal projection,if indicated, and simultaneously reduce the mandibular body height. Zigzag genioplasty allows one to properly correct excess of the chin(3-dimensionally), avoiding the need for muscular repositioning (except sometimes in types III and IV)(fig.4).A simple geometric calculation allows one to mobilize the chin in a vertical, horizontal, and sagittal direction,according to the needs of each patient. Furthermore, this design preserves the suprahyoid muscle attachmentsand the most important anatomic portion of symphysis area; narrowing the wide chin by this technique provides an esthetic and natural facial look.[1, 47]
3. Paranasal modification
Clinical evaluation: There is no specific soft tissue or skeletal cephalometric landmark(s) or values to quantify the “fullness” of this region, so deficiency assessment of para-alar region is mainly based on qualitative profile judgment.
Surgical technique: After general anesthésia and flap incision and elevation the osteotomy is done 2cm above the nasal floor from one side to another side To allow adequate mobilization the junction between septum and bony segment should be cut this can be done by a osteotomy.
4. Angle modification
Caucasians consider a prominent mandibular angle to be unappealing in their populations, and mandibular angle ostectomy has been popular since Baek et al. introduced it in 1989. Standard procedure to correct prominent mandibular angles is mandibular angle ostectomy with anoscillating saw through the intraoral approach, although a number of modifications and improvements in operative techniques have been reported in the last two decades.[68, 69]Kim et al. classified all the patients with prominent mandibular angle according to mandibular angle shape into four classes (I, II, III, and IV).
Clinical evaluation: For patients analysis it is important to consider the plans for correcting the lateral and frontal appearances of the lower face separately, because the ideal correction require two surgical techniques.
Surgical technique: Firstly, the ostectomy of the marginal part of the mandibular corpus-angle was performed, then corticectomy after evaluating the thickness of the resected bone fragment Mandibular corticectomy was performed to improve the frontal appearance. After designing the ostectomy line with a pencil, a groove was hollowed out on the lateral cortex using a round burr. 
4.1. Reduction malarplasty
Reduction body malarplasty (RBM) can be done for patients with a hyperplastic anterior mid-face. Reduction body and arch malarplasty (RBAM) is suited for patient with a hyperplastic anterior and posterior midface which will soften their square and wide facial appearance.[90, 94, 95]
Surgical techniques: since many years ago numerous surgical technique have been introduce to reduce the prominent malar.which some of these techniques are discussed here.
Zygoma shaving procedure: After intra oral flap elevation the entire zygomatic body and arch is exposed and subperiosteal dissection is carried out.  The most prominent portion of the zygoma, including part of the zygomatic arch, is shaved using a broad chisel or a bone bur. 
I-shaped osteotomy: Using a reciprocating saw, 2 parallel cuts are made on the zygomatic body from inner cortex toward the outer cortex resembling an I shape.  Then, the zygoma and the zygomatic arch complex are displaced antero-medially.
L-shaped osteotomy: This technique is similar to I-shaped osteotomy which can be considered in special cases.
C-shaped osteotomy The main difference of this technique with L-shaped osteotomy is in the oblique part of the osteotomy line; the oblique line is moved more toward the external orbital rims in comparison with the L-shaped osteotomy and consists of 2 parallel lines unlike L-shaped osteotomy in which we have only 1 line of osteotomy. 
Modified L-shaped Osteotomy: The modified L-shaped osteotomy differed from the original method mainly in that the two parallel osteotomy lines are made vertically so that the zygomatic body and arch can be shifted (Fig. 17).
Horizontal v-shaped osteotomy : this technique is similar to L-shaped osteotomy.
4.2. Aumentation malarplasty
Clinical evaluation: Oval shaped face with the key component of malar prominence is considered to be a sign of beauty and youth in Caucasians.  Many tricks using artificial highlighting and darkening are developed by makeup artists to accentuate the malar prominence.  Flattened cheeks and narrow face makes people look sad and prematurely aged.  This transverse midface deficiency can be addressed by widening the bimalar width.
|Hinderer||From the frontal view, draw a line from the lateral commissure of the lip to the lateral canthus of the ipsilateral eye and another line from the tragus to the inferior edge of the nasal ala. The area posterior and superior to the junction of these two projections should be the most prominent area of the malar eminence. (Fig. 12a) |
|Powell et al||Draw a vertical line through the middle of the face, then bisect the segment between the nasion and the nasal tip with a line that curves gently upward to the tragus on both sides. Draw a line from the inferior ala to the lateral canthus and another one, parallel to this one, from the lateral oral commissure toward the ear. The intersection of the curvilinear horizontal line and the line from the oral commissure marks the point where the malar area should be most prominent.(Fig. 12b) |
|Silver and Guilden||If the malar prominence in the true lateral projection is >5 mm posterior to the nasolabial groove, then a deficiency in the malar area exists. Silver describes the malar prominence triangle.  To create this triangle, draw a Frankfort horizontal line across the face in frontal projection and a parallel line that bisects the upper lip. Then draw a perpendicular line through both of these lines and through the lateral canthus. The intersection of the vertical line and the line through the upper lip defines point A.  Create a line from point A though the medial canthus and then a second line from point A toward the temporal area-but at the same angle from the vertical that was created by the projection from point A through the medial canthus. This creates the malar prominence triangle with the base being the Frankfort horizontal and the apex being point A. Silver advises that the implant should be placed several millimeters below the Frankfort line. (Fig. 12c) |
|Wilkinson||The ideal high points as he has suggested is at or just lateral to the outer canthus of the eye on a point a distant of approximately one-third from the lateral canthus to the inferior border of the mandible. (Fig.12d) |
|Schoenrock||On an oblique view (27 to 35 degrees of rotation from the frontal view) in natural head position,A line from themost lateral point of the malar complex intersected at 90° the commissure-canthus line at 66% of its lengthand The length of thisline was 17% the length of the commissure-canthus line. (Fig. 13) |
Malar recontouring involves not only the zygomatic region, but also the infraorbital,paranasal, and buccal regions. Furthermore, imperfections of other facial areas may reflect negatively on the malar region. The buccal region should be slightly concave or flat in adults,within the confines of a tangent from the cheekbone to the mandibular angle. Fullness in the buccal region can give the illusion of a poorly developed malar eminence. In these patients, partial excision of the buccal fat pad may be indicated. Shadowing in the concavity of the buccal area highlights the malar eminence, giving it a sculptured, well-defined look. Caucasian women tend to accentuate this effect by using makeup, whereas Asians prefer much softer contours. But excessive buccal hollowness results in an emaciated, gaunt appearance with exaggerated malar definition. Excessive width and prominence of the mandibular angle and masseter muscles make the malar eminence look small and give the face a square or triangular shape. Reduction of the mandibular angle and masseter muscles might be more adequate than malar augmentation. The malar eminence is also examined relative to the periorbital region. A high and prominent mala eminence enhances the appearance of the beautiful eye. Fullness of the area 10 mm lateral and 15–20 mm inferior to the lateral canthus should be obvious. (Fig. 21)
Zygomatic arch osteotomy: A subperiosteal flap is raised to expose the ascending malar buttress and the zygomaticomaxillary suture. The position of an oblique sagittal cut is selected by deciding whether augmentation should include any of the anterior buttress or whether it should be totally lateral to zygomaticomaxillary suture line. The cut is then made with a sagittal reciprocating saw starting from the inferior portion of the zygomaticomaxilary suture to the notch of both lateral orbital rim and malar zygomatic process. A previously selected graft may now be placed between the two segments. The result is an increase in interarch width (zygion-zygion).(Fig 22)
Zygomatic sandwich osteotomy (ZSO): To solve some problems, modifications of zygomatic arch osteotomy technique have been presented. Mommaerts et al modified Powell’s technique by connecting a vertical with a semihorizontal osteotomy which both transect the maxillary sinus, thereby maximizing anterior as well as lateral augmentation.
Zygomatic Sagittal Split Osteotomy (ZSSO):in this technique the zygomatic arch is isolated from its temporal origin to its zygomatic insertion both on its lateral and medial surfaces Using a waver sewer, a sagittal full thickness osteotomy of the zygomatic arch is performed (Fig. 26).Later, 2 separate partial thickness osteotomies: one on the arch’s osteotomies are connected with the previously released sagittal osteotomy. After correction of the zygomatic arch according to presurgical programs. Stabilization is achieved using bicortical titanium screws (Fig. 26).
5. Frontal modification
Frontal bossing reduction:Frontal Bossing known as a prominent supraorbital region and considers as a masculine characteristic. Generally men have more prominent frontal bossing than women which tends to have a smooth transition from brow area into a forehead. Frontal Bossing patients range from those with craniofacial anomaly such as thalassemias, Crouzon/ apert syndrome, Hurler syndrome to those without any underlying medical problem(figure 28,29). 
The most common method of brow bone reduction is an open approach using a bi-coronal flap with either a burring reduction, an infracture technique or osteotomies and reshaping. Simple burring can be effective if the outer table of the brow bone is thick enough.
In the course of normal skull growth, satisfactory reduction of anterior bossing without direct surgical correction of the shape of the forehead can be achieved through sagittal suturectomy along with biparietal barrel stave cuts. More correction of biparietal width and the occipital deformity, on the other hand, may also result in a gradual correction of the frontal deformity to satisfactory. In severe cases, however, the natural development of the calvarial shape with physiological skull growth following the described technique will not suffice as a cosmetically compromising frontal bossing will be most likely to persist. In such cases, a direct surgical correction, including radial osteotomies, rotation of bone flaps, “frontal to occipital switch”, π-procedure, morcellation, use of distraction or contraction devices, total cranial vault reconstruction, and other techniques have been suggested in the craniofacial literature. The general approach in these techniques includes excision, remodeling, transposition, and re-insertion of free bone flaps. The direct approach will then require complex bone fixations using wires or plates and screws. More advanced modifications of these techniques to avoid free bone flaps have been discussed where the shortened and re-approximated bone tongues stay attached at their normal calvarial position at the base or the apex of the calvaria. For example, in the technique described by Wagner and Wiewrodt in 2008, following sagittal suturectomy and parietalbarrel stave incisions, four or five lanceolate pieces of thefrontal bone are excised resulting in three or four vertical bone bridges. These osteotomies are designed to extend radially from thecranial base towards the fontanel. Small strips rectangular to the apico-basal axis are then cut out from these bridges, leaving basal and apical bone tongues.  The tabula externa at the base of the basal tongues is drilled off and the tongues are bent inward to correct the inferior aspect of the frontal bossing. 
Corresponding basal and apical bone tongues arethen re-approached and fixated with sutures.
The gold standard procedure for correction of severe frontal bossing is still open approach with osteotomy of the anterior table of the frontal sinus which provides excellent outcome. Complications such as long coronal scars, alopecia, blood loss, forehead paresthesia, neuromas and traction palsy of the facial nerve makes this operation invasive, with increased chance of morbidity and less desirable for mild to moderate frontal bossing correction. 
Despite the widespread use of endoscopic frontal bone operations such as remodeling of bony defects and removal of osteomas of the frontal bone, only recently has “endoscopic frontal bossing correction” been introduced. This emerging method seems to have rendered frontal bossing correction much simpler, significantly safer, and minimally invasive.
Moreover, the introduction of the endoscope revolutionized the surgical approach to the forehead, as it allowed for smaller incisions, magnified visualization, decreased risk of bleeding, faster recovery, and decreased chance of neuropathy by preserving cutaneous nerves. Endoscopic contouring of the forehead was first described by Song et al. on a Korean woman with frontal bone deformities. Since then, most published endoscopic manipulation of the frontal bone and supraorbital ridge has involved osteoma mass excision or frontal sinus fracture repair. Retrospective reviews of patients receiving endoscopic correction of frontal bossing have shown promising aesthetic results with minimal postoperative morbidity. This method of improving forehead contour, however, should be carried out on properly selected groups of patients. Mild deformities of frontal bossing and adequate bone thickness over the frontal sinus makes patients a great choice for endoscopic frontal bossing correction.  Some complications such as neurosensory damage, vascular injury, and extended operative time. . Similarities like incision line and dissection planes for this technique with standard endoscopic forehead lift allows easy access to the frontal bone for contouring in patients with frontal bossing and undergoing concurrent forehead rejuvenation.
The major architectural promontories of the facial skeleton, including the malar-midface region, nose, chin,angle of the mandible and frontal buttress provide the base upon which the soft tissues of the face drape. By altering these promontories, dramatic changes can be made in the estheticappearance of the face—much more so than by changing soft tissue and skin alone.Since many years ago numerous surgical and office based techniques have been introduce to augment, reduce or refine the most projected points of the face such as cheek,chin,nose, Para-nasal area, angle of the jaw.When reduction of these esthetic points is planed not only we don't have multiple choices but also without using these methods the precise and predictable correction is almost impossible. In case of augmentation although we have the more options such as soft tissue office based procedures or facial prostheses[110, 111] a precise pre-surgical evaluation in according to patient complaints, social and economic conditions, soft or hard tissue deficiency, amount of augmentation,the past similar procedure, ect. should be considered and the best method for each patient should be selected.Aesthetic adjunct facial osteotomy techniques have proved to be expedient techniques, with low morbidity, producing a controllable and predictable increase or decrease of the facial prominences and stable short and long-term morphological results.The most common complication of esthetic adjunct osteotomy techniques are under- correction and over-correction; pre-surgical evaluation and precise estimation of amount of excess or deficiency is a best method to reduce these complications the relation between hard and soft tissue change is also important,for example the hard tissue to soft tissue ratio in case of advancement genioplasty is almost 1:1 but in case of reduction genioplasty or chin narrowing is almost 1:0.5.Another complication is bad split ; although it is a rare complication and often is simple to manage but in cases in whom correction is impossible the best way is internat fixation,close the incision and set an another appointment with patient. Other complications such as nerve injury, relapse or sever bleeding is very rare. The more surgeon experience the less incidence of complications.
Special thanks to MS. Shahrzad Zojaji and Marjan Golpashafor illustrations.