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122
S. Park
12.8 Complication
andManagement
The most commonly observed complication following chin shortening surgeries is the sagging of
soft tissues, particularly the appearance of jowl
redundancy. To address this issue, methods such
as submental liposuction and thread lifting can be
employed for cosmetic enhancement. These techniques not only help in resolving the sagging but
also contribute to achieving a smoother facial
contour.
A specic complication often encountered in
reduction genioplasty is the attening of the
labiomental sulcus. This attening can lead to a
perceived reduction in chin volume and an unnatural prole. To address this issue and restore a
more natural chin prole, it may be necessary to
recreate the labiomental sulcus groove. This is
achieved by carefully burring the bone in the
required area. It is imperative during this process
to avoid damaging the tooth roots and to ensure
that the xation’s stability is not jeopardized by
excessive removal of the cortical bone. Such
meticulous attention in the surgical procedure is
key to maintaining the structural integrity of the
chin while simultaneously improving its aesthetic appearance.
12.9 Discussion
The pursuit of surgeries aimed at reducing facial
length has gained traction only in recent times. A
variety of techniques, such as forehead reduction,
hair transplantation, philtrum reduction, and
bone surgeries, have been tried, each delivering
varying degrees of satisfaction. A primary
obstacle in these procedures is insufcient bone
reduction, a challenge that has been progressively
addressed through innovative osteotomy designs
at our hospital. Equally important is the preservation of key aesthetic landmarks like the labiomental sulcus or the submental line, with
meticulous attention to these details markedly
enhancing the nal results.
An older, somewhat controversial method of
vertical reduction involves direct reduction or
shaving of the chin. While simple in its approach
and devoid of the need for multiple osteotomies
or metal screws, it is limited in its ability to
effectively shorten the chin. Shaving within the
cortical bone’s thickness achieves only minimal
reduction. Going deeper to the medullary bone
increases the risk of unpredictable bone resorption, potentially leading to irregular and asymmetric facial contours. Excessive soft tissue
detachment during this procedure may also
result in signicant soft tissue drooping. Given
these drawbacks, this technique, often favored
by less experienced surgeons, is not conducted
or recommended at ID Hospital for chin
reduction.
For philtrum reduction, we recommend a
maximum reduction of 6mm to maintain a natural appearance and minimize scarring. Reductions
beyond 6 mm are typically discouraged due to
the likelihood of causing unappealing soft tissue
bunching in the philtral area. Long-term relapse
of the shortened lip is a common occurrence,
worsened by more extensive reductions.
Therefore, in surgical planning, an overcorrection of approximately 20% is prudent to anticipate this relapse. Moreover, to avoid noticeable
scarring, particularly widening at the base of the
columella, ensuring a tension-free margin postkey suture is crucial. These factors—the risk of
relapse and scarring—are possibly why many
surgeons are hesitant to perform vertical reduction for a long lip. However, signicant improvements can be realized through a combination of
facial bone contouring surgery, diverse chin osteotomy techniques, and meticulous soft tissue
management.
References
1. Larrabee WF, Makielski KH, Henderson JL.Variations
in facial anatomy with race, sex, and age. In: Larrabee
WF, Makielski KH, Henderson JL, editors. Surgical
anatomy of the face. Philadelphia: Lippincott Williams
& Wilkins; 2004. p.22–8.
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12 Consideration inTreatment ofLong Face
123
2. Prendergast PM. Facial proportions. In: Erian A,
Shiffman MA, editors. Advanced surgical facial rejuvenation: art and clinical practice. Berlin: Springer;
2012. p.15–22.
3. Farkas LG, Hreczko TA, Kolar JC, Munro IR.Vertical
and horizontal proportions of the face in young adult
North American Caucasians: revision of neoclassical
canons. Plast Reconstr Surg. 1985;75(3):328–38.
4. Sim RST, Smith JD, Chan ASY.Comparison of the aesthetic facial proportions of Southern Chinese and white
women. Arch Facial Plast Surg. 2000;2(2):113–20.
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t.me/Dr_Mouayyad_AlbtousH
Alloplastic Modication ofLower
Face
SanghoonPark
13
13.1 Pearls
1. Facial skeletal augmentation with alloplastic
implants is instrumental in improving facial
projection, denition, or balance.
2. Alloplastic implant insertion stands as a primary option for various cases of mandibular
skeletal deciencies due to its simplicity and
the absence of donor site requirements.
3. Silicone, Medpor, and Gore-Tex are the most
frequently used materials in lower facial augmentation. The selection of the implant material is contingent on factors like the recipient
site, softness, availability, and biologic
behavior.
4. The key to successful augmentation lies in
meticulous pocket dissection adequate for the
implant.
5. Fixation to a stable structure is typically recommended in most augmentation cases.
6. The chin is prevalently chosen for alloplastic
implantation, necessitating careful consideration of the implant’s position, prole, and
shape based on patient needs.
7. Mandible implants are utilized for enhancing
masculinity or to correct excessive mandibular reduction.
S. Park (*)
Center for Facial Bone Surgery, Department of
Plastic Surgery, ID Hospital, Seoul, South Korea
e-mail: spark@idhospital.com
8. Infection management is critical, necessitating preemptive treatment with an adequate
dosage and duration.
13.2 Introduction
Patients with mandibular skeletal deciencies
often turn to various methods for aesthetic
improvement. While facial bone surgeries like
double-jaw surgery or genioplasty offer effective
and permanent solutions, many patients initially
favor alloplastic implant insertion. This preference stems from its simplicity, cost-effectiveness,
and shorter recovery time, making it suitable for
simple and localized deciencies. Alloplastic
implants have an advantage over autologous fat
grafts or llers, as they provide a more permanent
and denitive facial contour without the drawbacks of donor site morbidity or limitations.
Chin implants, a common application of alloplastic materials, are traditionally used for
enhancing chin projection and length. Nowadays,
they are also employed to alter the frontal shape
of the chin, affecting aspects like pointedness,
width, and contour. Implants are the preferred
method for many surgeons, especially when
mandibular hypoplasia is mild and localized to
the chin area [1].
Mandibular augmentation with implants is
typically pursued by male patients seeking to
accentuate masculinity. However, in Asian populations where a slim lower face is favored, this
© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024
S. Park (ed.), Facial Bone Contouring Surgery, https://doi.org/10.1007/978-981-97-4992-8_13
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S. Park
augmentation is less common. Alloplastic
implant insertion for creating a dened, robust
jawline is particularly rare among Asian women.
It is often considered as a corrective measure following overzealous mandibular reduction [2, 3].
Various implant materials are used, including
solid silicone, porous polyethylene (Medpor®),
and Gore-Tex®. Solid silicone implants, known
for their easy availability and sculptability, are a
popular choice in many Asian countries,
particularly for chin surgeries [4]. Medpor®
stands out for its stability, inertness, and porosity,
which facilitates xation and reduces capsule
formation [5]. Additionally, it can be shaped
using heat during surgery. Gore-Tex®, an
expanded synthetic polymer, is available in various forms and is favored for its softness, exibility, and adaptability, making it ideal for
augmenting difcult-to- shape defects or areas
with thin overlying skin [6, 7]. Implant xation
can be achieved with sutures to adjacent soft tissue or screws to the underlying bone.
13.3 Patient Assessment
andConsultation
Surgeons must engage in detailed discussions
with patients to fully understand their exact needs
and desires. A direct physical examination is crucial for evaluating specic patient issues and formulating an appropriate surgical plan. It is vital
to rule out any bite problems, which may necessitate different treatment. The degree of chin
hypoplasia is assessed in terms of its projection,
length, and, more recently, its frontal shape,
including width and contour. If the patient has
occlusion issues, such as class II malocclusion,
and signicant hypoplasia, a simple chin implant
may not sufce to correct the problem, and satisfaction may be limited. In cases where hypoplasia extends to the mandible body or angle, a
prefabricated implant might be required. The
functionality of the mentalis muscle and lip competency are also crucial factors to consider.
Hyperactive mentalis muscle might contribute to
implant encroachment on the chin, potentially
necessitating implant removal. Clinical photo-
graphs are indispensable for a comprehensive
assessment and for planning the surgical
approach. Radiological examinations, such as
cephalometric and panoramic radiographs, are
invaluable for accurate facial prole analysis. It’s
also important to rule out any jaw deformities
involving the temporomandibular joint (TMJ)
and to carefully trace the course of the inferior
alveolar canal. The condition of the incisor tooth
roots should be evaluated, as there is a risk of
aggravated tooth root resorption following chin
implant surgery. Surgeons are responsible for
informing patients about potential complications
specic to the use of implants. This includes discussing the incidence of infection and the possibility that implant removal may be necessary.
Patients should be made fully aware of these risks
and their implications to make an informed decision about their treatment.
13.4 Surgical Techniques
Facial skeletal augmentation can be performed
under either local anesthesia with sedation or
general anesthesia. Simple chin implant procedures may only require intravenous sedation and
local anesthesia, but general anesthesia may be
necessary for complex implants or mandible
implants. This surgery is typically done on an
outpatient basis. The approach to the chin can be
either through a submental or intraoral incision.
However, recently, a submental incision is rarely
used due to visible scarring. The intraoral
approach for implant insertion does not increase
the risk of infection. An intraoral incision is
placed about 1cm above the sulcus for adequate
tissue safety in closure [8]. The area for alloplastic implant insertion is dissected in the subperiosteal plane. Some surgeons prefer to place implants
in soft tissue pockets, but clinical experience
shows that subperiosteal placement enables the
accurate placement and minimizes the displacement by muscle movement. Rigid xation of the
implant is preferred (Fig. 13.1). It prevents
implant mobility, particularly important for chin
implants which can move upward due to mentalis
muscle pull if not secured. Rigid xation also
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13 Alloplastic Modication ofLower Face
127
enhances the adaptation of the implant to the
bone surface, reducing the risk of dead space,
which can lead to hematoma collection and infection. Improper adaptation can result in contour
issues like overcorrection, asymmetry, or
irregularities.
The subperiosteal pocket is carefully shaped
to the exact dimensions of the implant using ne
surgical instruments like a Freer elevator. An
overly spacious pocket increases the risk of
implant mobility and makes precise positioning
challenging. Conversely, a tight pocket can cause
the implant to buckle or catch overlying tissue,
leading to contour issues. It’s crucial to inspect
Fig. 13.1 Rigid xation with screws is preferred to prevent implant mobility, over-correction, asymmetry, or
irregularities
the margins of the implant carefully after
placement.
13.4.1 Chin
When augmenting the chin with alloplastic
implants, precise control over the implant’s position is crucial, tailored to achieve the desired chin
shape. For chin lengthening, the implant is positioned vertically beneath the chin (Fig. 13.2,
right). If the focus is solely on enhancing projection without altering the chin’s length, the implant
is situated anterior to the mental protuberance
(Fig. 13.2, center). In cases requiring improvement in both length and projection, which is most
frequent cased, the implant is placed anteroinferior to the mental protuberance (Fig.13.2, left).
To secure the implant and prevent its superior
displacement or rotation, it is immobilized with
two titanium screws.
Another important consideration is the frontal
width of the implant, which varies based on the
degree of mandibular hypoplasia. In moderate to
severe cases, a wider implant that extends lateral
to the mental foramen can provide more comprehensive augmentation. Conversely, for patients
with a at and short mandible or those desiring a
slim, pointed chin, a narrow high-prole implant
Fig. 13.2 The position of the implant is determined by the direction of the improvement to be achieved
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128
S. Park
is preferable for achieving the desired lower face
and chin aesthetics.
13.4.2 Mandibular Implant
The surgical exposure of the mandible’s ramus
and body is optimally achieved via an intraoral
incision, thoughtfully positioned about 1 cm
above the sulcus. The subsequent step of subperiosteal dissection is pivotal, aiming to delicately
detach muscle attachments from both the inferior
and posterior borders of the mandible. This
approach not only ensures the precise placement
of the implant but also minimizes potential damage to the surrounding tissues.
The robust nature of the masseter muscle
necessitates particular attention during the
implant procedure. Its forceful pull could lead to
displacement or misalignment of the implant.
Therefore, securing the implant meticulously
with multiple screws is a fundamental step to prevent movement, ensuring the implant remains
rmly in its desired location. The limited visibility and maneuverability in this area pose a challenge; however, tools like a right-angle
screwdriver can signicantly facilitate the process. In cases where such tools are unavailable,
multiple xations along the implant’s upper border should be considered to provide adequate
stability.
The choice of the implant’s shape and material
is tailored to the patient’s unique anatomical
needs and aesthetic goals. For cases with decient
lateral mandibular volume, a simple silicone
implant may sufce. In more complex scenarios,
such as when there’s a signicant loss of the mandible’s lower and posterior border, a sturdier
option like a Medpor® implant is advised. This
choice becomes particularly important when
larger defects of the lower border are present,
requiring the implant to serve as a buttress against
muscle pull. A Medpor® implant with an integrated lower border sleeve is ideal in such situations (Figs. 13.3 and 13.4). The importance of
rigid xation cannot be overstressed to ensure the
long-term success and stability of the implant.
Postoperative care is a critical component of
the surgical process. Suction drains should be
considered seriously if bleeding occurs and
meticulous hemostasis is not accomplished, as
hematoma formation near the implant may result
in subsequent infection. Elastic bandage with
multiple sponges helps to reduce the dead space
and reduce the postoperative bleeding. Postsurgical hygiene is facilitated through the pre-
ab
Fig. 13.3 Implants for augmentation of mandible are also xed with multiple screws (a) preop, (b) after insertion of
Medpor implant and xation with screws
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13 Alloplastic Modication ofLower Face
Fig. 13.4 Medpor® implant with lower border sleeve
scription of chlorhexidine gluconate mouthwashes
for use starting 3days after the operation. A regimen of intravenous antibiotics, followed by a
course of oral antibiotics, is administered to further mitigate the risk of infection and promote
healing. This comprehensive approach to surgery
129
and aftercare underscores the commitment to
patient safety and aesthetic excellence.
13.5 Key Technical Points
1. Rigid xation is recommended with proper
pocket dissection to prevent displacement and
visible margin.
2. Aseptic technique is critical to prevent the
infection. Be careful not to contaminate the
implant with too many test insertions.
3. Selection of proper implant (shape and size) is
based on preoperative evaluation and patient’s
request and surgeon’s experience.
4. Mentalis muscle should be carefully repaired
and controlled to have a natural lip and chin
shape.
5. Fixation of the mandible implant should be
strong enough to withstand the strong pull of
masseter muscle.
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130
13.6 Case Study
Case 1
A 24-year-old woman complained of decient projection of chin (Fig. 13.5a). She wanted
improvement of the prole. Considering ideal prole through lateral X-ray (Fig.13.5b), 8mmsized silicone implant was inserted through intraoral incision and xed with two screws
(Fig.13.6b). The chin projection was improved markedly after the surgery (Fig.13.6a).
ab
S. Park
Fig. 13.5 (Case 1) Preoperative photo (a) and lateral X-ray. (b) Suction
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ab
13 Alloplastic Modication ofLower Face
ab
Fig. 13.6 (Case 2) Preoperative (a) and postoperative (b) photo
131
Case 2
Mandibular angle augmentation
A 28-year-old man complained of feminine appearance because of lack of mandibular angle
and wanted more strong jaw line (Fig.13.7a). He underwent a Medpor implant insertion surgery
at angle. Through the oral incision, Medpor implants were inserted bilaterally and xed with
two screws to prevent instability. After the surgery, his jawline was improved denite and masculine (Fig.13.7b).
Fig. 13.7 (Case 2) Preoperative (a) and postoperative (b) photo
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