Basics of facial plastic surgery

After taking into account all general considerations, the facial areas are assessed. The practical method consists of a systematic assessment of individual aesthetic units of the face.

These units are the forehead and eyebrows, the periorbital region, the cheeks, the nose, the perioral region and the chin, and the neck. However, it should be remembered that it is necessary to take into account how the features of the various units interact with each other, creating a harmonious or disharmonious appearance.

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Forehead plastic surgery

Perhaps no other area of the face experiences as much surgical intervention as the aging forehead and eyebrows. Knowledge of the anatomy and aesthetics of the upper third of the face is essential to performing adequate rejuvenation surgeries. The layers of the frontal region are an extension of the layers of the scalp. The mnemonic word "SCALP" describes the five layers of the forehead: S (skin), C (subcutaneous tissue), A (galea aponeurotica), L (loose areolar tissue), and P (pericranium). The skin is attached to the subcutaneous tissue. The tendinous helmet surrounds the entire cranial vault, interweaving with the frontal and occipital muscles anteriorly and posteriorly. Below the superior temporal line, the helmet becomes the temporoparietal fascia. The loose areolar tissue (subhelmet layer) lies between the tendinous helmet and the periosteum. It is an avascular layer that allows the helmet and more superficial tissues to glide over the periosteum. The periosteum is a thick layer of connective tissue attached to the outer plate of the cranial vault bones. At the point where the superior and inferior temporal lines meet, the periosteum merges with the temporal fascia. The periosteum also becomes continuous with the periorbital fascia at the level of the superior orbital rim.

The forehead and eyebrow movements are provided by four muscles: the frontalis, procerus, corrugator supercilii, and orbital part of the orbicularis oculi. The paired frontal muscles have a clear division along the midline. The frontal muscle originates from the tendinous helmet and unites inferiorly with the procerus, corrugator supercilii, and orbicularis oculi. The frontal muscle has no bony attachments. It interacts with the occipital muscle through attachment to the tendinous helmet, displacing the scalp. The frontal muscle elevates the eyebrow. Transverse frontal folds are caused by chronic contraction of the frontal muscle. Loss of innervation of the frontal muscle leads to drooping of the eyebrows on the damaged side.

The paired corrugator supercilii muscle originates from the frontal bone near the upper inner edge of the orbit and passes through the frontal and orbicularis oculi muscles, inserting into the dermis of the middle part of the eyebrow. It pulls the eyebrow medially and downwards; excessive tension (movement of the eyebrows) causes the formation of vertical furrows above the bridge of the nose. The procerus muscle is pyramidal in shape and originates from the surface of the upper lateral cartilages and bones of the nose, inserting into the skin in the region of the glabella. Contraction causes the medial edges of the eyebrows to descend and horizontal lines to form above the root of the nose. The orbicularis muscles surround each orbit and pass onto the eyelids. They originate from the periosteum of the medial edges of the orbits and insert into the dermis of the eyebrows. These muscles are subdivided into the orbital, palpebral (upper and lower) and lacrimal parts. The upper medial fibers of the orbicularis muscle lower the medial part of the eyebrow. These fibers are called the depressor supercilii. The corrugator supercilii, procerus, and orbicularis oculi work together to close the eye and are antagonists to the frontalis movements; their overuse causes horizontal and vertical lines across the bridge of the nose.

The classically described position of the female eyebrow has the following criteria: 1) the eyebrow begins medially at a vertical line drawn through the base of the ala of the nose; 2) the eyebrow ends laterally at an oblique line drawn through the outer corner of the eye and the base of the ala of the nose; 3) the medial and lateral ends of the eyebrow are approximately at the same horizontal level; 4) the medial end of the eyebrow is club-shaped and gradually thins laterally; 5) the apex of the eyebrow lies on a vertical line drawn directly through the lateral limbus of the eye. Some believe that the apex, or top, of the eyebrow should ideally be more laterally; that is, the apex lies on a vertical line drawn through the outer corner of the eye, which is opposite the lateral limbus.

Some classic criteria apply to men, including the location of the apex, although the entire brow has minimal arch and is located at or just above the superior orbital rim. Excessive lateral elevation of the brow, causing a brow arch, can feminize the male brow. Excessive medial elevation produces a "stricken" appearance. Compared to men, women's foreheads are smoother and more rounded, with less pronounced brow ridges and a less acute nasofrontal angle.

The two major age-related changes of the upper third of the face are brow drooping and lines due to facial overmobility. Brow drooping is primarily caused by gravity and loss of the elastic component of the dermis. This may give a frowning or angry appearance to the eyes and brow. The brow should be examined for any asymmetry that accompanies bilateral drooping. In unilateral drooping, etiologic factors (such as temporal branch palsy) should be considered. What may initially appear to be excess upper eyelid skin (dermatochalasis) may actually be drooping of the forehead skin. Clinically, this is most obviously seen as "lateral bags" over the upper eyelids. These may be large enough to limit the superolateral visual fields, providing a functional indication for surgical intervention. Attempts to excise the saccular skin folds solely by blepharoplasty will only pull the lateral edge of the eyebrow downward, worsening the brow ptosis.

In addition to drooping eyebrows, the aging upper third of the face is characterized by lines of increased mobility. These furrows are caused by repeated skin tension exerted by the underlying facial muscles. Chronic contraction of the frontalis muscle in the upward position results in the formation of transverse furrows on the forehead: in short, the frontalis muscle provides its own, non-surgical lift. Repeated frowning overuses the procerus and corrugator muscles. This, accordingly, results in the formation of horizontal furrows at the root of the nose, as well as vertical furrows between the eyebrows.

In case of excess upper eyelid skin, additional procedures such as blepharoplasty are necessary, as it allows to disguise the incision in the eyebrow area. The height of the forehead should also be assessed, because some interventions not only perform a lift, but also secondarily improve (increase or decrease) the vertical height of the forehead. In general, while all forehead surgeries raise the armor and the forehead, brow lifts have different effects (if any) on the forehead.

Plastic surgery of the periorbital region

The periorbital region includes the upper and lower eyelids, the inner and outer corners of the eyes, and the eyeball. Again, the size, shape, location, and symmetry of the individual components must be assessed. The assessment must take into account the features of the remaining facial areas. The distance between the corners of the eyes should roughly correspond to the width of one eye. In Caucasians, this distance should also be equal to the distance between the wings of the nose at its base. In Negroids and Mongoloids, this rule is not always true due to the wider base of the nose.

The main muscle in this area is the orbicularis oculi. This muscle is innervated by the temporal and zygomatic branches of the facial nerve. The orbital portion of this muscle surrounds the orbit and contracts like a sphincter, causing blinking. This portion of the muscle attaches laterally to the skin of the temporal and zygomatic region, which creates wrinkles and crow's feet as the face ages.

The earliest signs of aging often appear on the eyelids. This is mainly due to sagging skin (dermatochalasis), the formation of false herniated orbital fat through the orbital septum, and hypertrophy of the orbicularis muscle. The most common problem of the upper eyelids is dermatochalasis, followed by the formation of protruding fat pads. This problem is well treated by traditional upper blepharoplasty with liposuction.

In the lower eyelids, skin, fat, and muscle problems are often seen in isolation or in combination. Isolated pseudofat hernias are often seen in relatively young patients and are treated with transconjunctival blepharoplasty. Small dermatochalasis can be treated with limited skin excisions, chemical peels, or laser resurfacing. Many very young patients have isolated hypertrophy of the orbicularis oculi muscle, usually following frequent sideways glances. This is often seen in people who smile professionally, such as news anchors or politicians. This hypertrophy manifests as a thin ridge along the lower eyelid margin, which requires muscle excision or volume reduction.

Malar bags must be distinguished from scallops. Malar bags are swollen, sagging areas bordering the aesthetic area of the cheek that accumulate fat or fluid with age. They sometimes require direct excision. Scallops, on the other hand, usually contain invaginated muscle and skin. They can be corrected during extended lower blepharoplasty.

Other periorbital problems should be evaluated, including drooping eyelids, anophthalmos, proptosis, exophthalmos, drooping or displacing the lower eyelids, and lateral pouching. As noted above, lateral pouching is caused by drooping eyebrows as well as excess eyelid skin. A common test used to evaluate lower eyelid drooping is the pinch test, where the lower eyelid is grasped between the thumb and forefinger and pulled away from the globe. An abnormal result is a delayed return of the eyelid to the globe or a return only after blinking. Exposure of the sclera beneath the lower eyelid or ectropion (eversion of the eyelid margin) is also noted. Approximately 10% of the normal population has scleral exposure beneath the lower eyelid that is not related to age. Enophthalmos may represent previous orbital trauma and may require orbital reconstruction. Exophthalmos may be due to Graves' orbitopathy, necessitating endocrinologic evaluation. Incorrect position of the eyeball or dysfunction of the extraocular muscle requires consultation with an ophthalmologist and obtaining images of the orbit.

Ptosis, entropion (inversion of the eyelid margin), ectropion and excessive drooping of the lower eyelid can be corrected during blepharoplasty. Lines of excessive mobility, such as crow's feet, cannot be eliminated without intervention on the facial muscles. This can be achieved by paralysis or destruction of the branches of the facial nerve that innervate the muscles. In practice, the method of chemical paralysis with botulinum toxin is used.

Plastic surgery of cheeks

The cheeks form an aesthetic unit that extends to the parotid fold laterally, to the nasolabial fold medially, and to the zygomatic arch and the inferior margin of the orbit superiorly and to the inferior margin of the mandible inferiorly. The most prominent landmark on the cheek is the zygomatic (malar) eminence. The zygomatic eminence consists of the zygomatic and maxillary bones. A pronounced zygomatic eminence is a sign of youth and beauty. The zygomatic eminence gives shape and strength to the face. Underdevelopment of the cheekbones may be caused by underdevelopment of the anterior surface of the maxillary bone or, laterally, by underdevelopment of the zygomatic prominence.

The muscles of the cheek can be divided into three layers. The deepest layer consists of the buccinator muscle (muscle of the trumpet), which comes from the deep fascia of the face and intertwines with the orbicularis oris at the oral commissure. The next layer is represented by m. caninus (according to the Paris nomenclature - the muscle that raises the angle of the mouth), which comes from the canine fossa and the quadratus labii superioris, which has three sections that come from the area of the upper lip (according to the Paris nomenclature, these are the zygomaticus minor muscle, the muscle that raises the upper lip, and the muscle that raises the upper lip and the ala of the nose).

Both the caninus and the quadratus labii superioris insert into the orbicularis oris. Finally, the zygomaticus major and the laughter muscle join at the lateral commissure. All these muscles arise from bony prominences on the maxilla or the pterygomandibular suture. They end either in the superficial fascia of the perioral skin or in the deep muscles of the upper lip. They are innervated by the zygomatic and buccal branches of the facial nerve. These muscles cause the middle third of the face to move upward and laterally, giving it a happy expression.

The buccal fat pad is a permanent component of the masticatory space. Interestingly, its severity is not related to the general degree of obesity of a person. It consists of the main part and three main processes: temporal, buccal and pterygoid. Significant cheekiness may be partly due to the descent of the buccal fat. Clinically, the descent of the buccal fat may appear as excess volume of the lower part of the cheeks or as cheeks that are full in the middle part of the body of the mandible.

The buccal fat pad is found through an intraoral incision above the third maxillary molar. The structures of surgical importance here are the parotid duct and the buccal branch of the facial nerve. It is therefore important not to pursue all the buccal fat but to remove only the fat that tends to protrude.

Depending on the nasolabial border and the severity of the nasolabial fold, the part of the cheek lateral to and immediately adjacent to the border, consisting of the malar fat pad and the skin overlying it, undergoes age-related changes. The nasolabial fold is probably the most visible fold on the face. It results from direct attachment of the facial muscles to the skin or from the forces of movement transmitted by the superficial muscular aponeurotic system (SMAS) to the skin through vertical fibrous septa. With age, fat atrophies in the upper and middle parts of the face and is deposited in the submental area. The formation of a submalar depression with aging results in the appearance of sunken cheeks.

The malar eminence can be augmented with implants that can be placed via an intraoral approach. Rhytidectomy with proper tension direction in combination with malar eminence augmentation can help reduce the severity of the nasolabial fold. The nasolabial border can be directly smoothed by implantation or extended rhytidectomy. Complete elimination of this fold is not possible; in fact, it is probably not desirable, since it is an important facial element separating the buccal aesthetic unit and the nasolabial region. Rhytidectomy can also improve the definition of the lower border of the mandible and reposition the buccal fat pad.

Plastic surgery of the nose

The nose is the most prominent of the facial aesthetic units because of its central position in the frontal plane and its prominence in the sagittal plane. The slightest asymmetry and deviations are more noticeable here than in other areas of the face. The proportions of the nose should be in harmony with the rest of the face and the structure of the body. A long, thin nose looks out of place on a short, stocky person with a wide face, as does a wide, short nose on a tall, slender person with an elongated face.

The muscles of the nasal pyramid are rudimentary in nature and have little influence on the static and dynamic appearance of the nose. Exceptions are the muscles that dilate the nostrils and depress the nasal septum, which originate from the upper lip and extend to the bottom of the nose and the nasal septum.

The nose is usually described by its length, width, projection, and rotation. Various angles and measurements are used to describe the nose and its relationship to the rest of the face. In general, the bridge of the nose allows a gentle downward curve from the medial border of the eyebrows to the area above the tip. A slight hump at the bone-cartilaginous junction is acceptable in both sexes, but is probably more appropriate in men. The tip should be in two parts, and ideally 2-4 mm of the base of the septum should be visible in profile. In Caucasians, the base of the nose approaches an equilateral triangle. A wider distance between the alae is normal in Asians and Negroids. In shorter people, greater rotation of the nasal tip is perceived better than in taller people.

Over time, the cartilaginous framework of the nasal tip weakens, causing the tip to widen, droop, lengthen, and potentially obstruct the airway. The nostrils may widen, and the angle between the base of the nose and the upper lip may become more acute and droop. Thickening of the skin of the nose may also occur, as in rosacea.

A prominent nose combined with a hypoplastic mandible is aesthetically unsuitable and can usually be corrected by combining reduction rhinoplasty with augmentation mentoplasty. In contrast, nasal reduction should be restrained in patients with a prominent mandible and chin to maintain facial balance and harmony and to prevent worsening of the prognathic appearance, especially in profile.

Plastic surgery of the perioral area and chin

The perioral region includes the part of the face from the subnasale and nasolabial folds to the menton, the lower border of the soft tissue contour of the chin. The contours of the chin are determined by the shape and position of the mandibular bone and, in the case of chin recession, the soft tissues that cover it. After the nose, the chin is the most common cause of abnormalities in profile examination.

The muscles responsible for facial movements around the mouth include the mentalis, the quadratus labii inferioris, and the triangular muscles that lie in the plane deeper than the platysma (according to the Paris nomenclature, the last two groups are the muscle that depresses the angle of the mouth, the muscle that depresses the lower lip, and the transverse muscle of the chin). These muscle groups are woven into the orbicularis oris in the area of the lower lip. These muscle groups are innervated by the marginal branch of the lower jaw, from the facial nerve system. These muscles contract and depress the lower lip. All of them are embedded in the lower edge of the mandibular bone.

The literary equivalent of the term microgenia is "small chin". In patients with normal occlusion (Angle class I: the mesiobuccal cusp of the first maxillary molar is aligned with the mesiobuccal groove of the first mandibular molar), microgenia is diagnosed by drawing a vertical line from the vermilion border of the lower lip to the chin. If this line passes anterior to the soft tissue pogonion, microgenia is diagnosed. Particular attention should be paid to the lateral view before surgery, since the surgeon's task is to push the chin up to the vertical line of the lower lip. In men, slight hypercorrection is acceptable, while in women, hypocorrection is more acceptable.

The overall balance of the face in profile is best assessed by additionally taking into account the projection of the nasal dorsum. Many times, computer reconstruction of images has helped to illustrate the possible positive contribution of chin augmentation to the results of rhinoplasty. The main surgical approaches to correct microgenia are implantation and genioplasty. For alloplastic implantation in the mandible, silastic is most often used.

Mandibular hypoplasia is an acquired condition secondary to varying degrees of bone resorption in the mandible. Adequate orthodontic retention can help combat the overall decrease in mandibular size, particularly in alveolar bone height. With age, there is also progressive soft tissue atrophy and bone loss in the area between the chin and jaw. The resulting groove is called the premaxillary groove. This is important because although a well-done facelift can improve the mandibular area, this conspicuous groove will remain.

The examination of a patient with mandibular hypoplasia is similar to that of microgenia, with particular attention to the presence of a normal occlusion. Mandibular hypoplasia should not be confused with retrognathia. The latter condition produces an Angle Class II occlusion and is corrected by bone grafting such as a sagittal split osteotomy.

The surgical approach to mandibular hypoplasia is the same as that described for microgenia. The main difference is the type of silastic implant used. If there is significant hypoplasia of the mandibular body, a larger implant is selected. The shape of the implant also helps to correct microgenia secondarily if indicated. Some patients do not have a pronounced mandibular angle (usually congenitally) and may benefit from this.

Like mandibular hypoplasia, occlusion plays an important role in the formation of the lower face. Orthodontic correction, in addition to normalizing occlusion, can restore normal lip relationships. Changes in occlusion, especially associated with bone resorption in the edentulous lower jaw, can disrupt the proportions of the middle and lower parts of the face. Resorption of the alveolar bone, a decrease in the vertical distance between the upper and lower jaws, and significant soft tissue disorders may occur. Such changes can only be partially compensated for by dentures.

With age, the upper lip lengthens, the vermilion border of the lips becomes thinner, and the middle part of the face shifts (retrusions). Perioral wrinkles also form, extending vertically from the edge of the vermilion border of the lips. Another phenomenon is the appearance and deepening of the "marionette" lines, which are a bilateral downward continuation of the nasolabial folds, similar to the vertical lines at the bottom of the face of a ventriloquist's doll. The chin and cheekbones may protrude less as a result of redistribution of the skin and subcutaneous tissues covering them. A decrease in the height of the skeletal component of the middle and lower parts of the face is noted.

Most lip surgeries are performed to reduce or enlarge the lips. Full lips are currently preferred. The upper lip should be fuller and project slightly forward over the lower lip in profile. Lip augmentation is performed using a variety of materials, including autologous skin and fat, homo- or xenocollagen, and porous polytetrafluoroethylene.

Neck plastic surgery

Restoration of the cervicomental angle is an important component of rejuvenation surgery. The neck in youth has a well-defined mandibular line, which casts a submandibular shadow. The skin in the submental triangle is flat and taut. The subcutaneous muscle (platysma) is smooth and has good tone. In addition, the muscles attached to the hyoid bone create a cervicomental angle of 90° or less. These factors give the neck a youthful contour and appearance.

An unattractive neck may be the result of congenital or acquired anatomical causes. Congenital causes include a low position of the hyoid-thyroid complex and accumulation of cervical fat, both above and below the platysma muscle. With age, the expected acquired changes occur in the lower face and neck. These include prolapse of the hyoid gland, striations of the platysma muscle, and excess skin. Neck appearance is also greatly affected by microgenia, mandibular hypoplasia, malocclusion, chin recession, and premental groove, which were discussed above.

Patients should always be evaluated for these conditions. Standardizing a preoperative evaluation plan for the lower face and neck area will ensure that the correct surgical technique is selected. The assessment prior to surgical neck rejuvenation is performed according to the following plan: 1) assessment of the adequacy of skeletal support, 2) the need for SMAS-platysma muscle complex engagement, 3) the need for fat contouring, and 4) the need for skin tightening.

The ideal position of the hyoid bone is the level of the fourth cervical vertebra. Patients with an anatomically low position of the hyoid bone have an obtuse cervicomental angle, which limits surgical options. The main surgical approach to contouring fat tissue is liposculpture, either by liposuction or direct lipectomy. Surgical correction of the striations of the platysma muscle consists of a limited anterior horizontal myotomy with excision of the raised hypertrophied muscle edges. The newly formed anterior edges of the platysma muscle are connected with sutures. Tensioning the platysma muscle will also help correct the prolapse of the hyoid gland.

The preferred method of removing excess neck skin is the upper lateral facelift flap. This bilateral tension lifts the skin component of the chin-chin "pendant." If excess skin remains on the anterior neck, a submental incision with localized skin excision is required. Excessive skin excision should be avoided, as it results in the formation of protruding cones at the sides of the sutured incision. Excessive skin excision may also alter the neck line, disrupting the youthful chin-chin contour.

In some patients with fat deposits in the neck and young elastic skin with minimal excess, liposuction alone may be required. This type of skin is not yet relaxed and retains shape memory. Local excision of the skin is not required here, as the skin of the neck will be pulled upward and retain the submental contour.

Ear plastic surgery

Cosmetic surgery may be useful for some patients with prominent ears. The apex of the auricle should be level with the outer end of the eyebrow. The inferior insertion of the ear should be level with the junction of the ala of the nose with the plane of the face. In profile, the ear is tilted backward. It is important to remember during rhytidectomy not to create a forward-pull appearance of the ears, which would reveal the fact of surgical intervention. The width/length ratio for the ear is 0.6:1. The ears should form an angle of about 20-25° with the skin of the back of the scalp, and the middle part of the ear should be no more than 2 cm from the head.

With age, the size of the ears increases. Their protrusion also increases due to an increase in the concho-scaphoid angle, and the antihelix fold may be partially lost. Changes in the ear lobe may be associated with long-term wearing of earrings.