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21 Alloplastic Modication oftheMidface
211
Fig. 21.3 Suborbital augmentation. (a) Note that the
infraorbital nerve should be identied and preserved during the subperiosteal dissection. To avoid irritation or
compression to the infraorbital nerve, the superior border
of the implant should be trimmed. The posterior surface of
implant should be carved to obliterate the dead space
above the anterior surface of the zygoma. Implants are
xed with titanium screws in two points for immobilization. (b) Implants may be positioned on zygomatic body
to augment the maximum malar projection
Fig. 21.4 Implants for suborbital augmentation. The
implants used in ID hospital are shown. It is also made of
silicon like paranasal implants. Unlike the paranasal
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implants, the shape is ovoid to rectangular with round border. The thickness of implants ranges from 2 to 6mm
212
S. Park
21.5 Key Technical Points
1. The success of facial augmentation largely
hinges on the appropriate selection and placement of implants. The right choice of implant
in terms of size, shape, and material, as well
as its accurate positioning, is essential to
achieving the desired aesthetic outcome and
ensuring the long-term stability of the implant.
2. The dissection should be sufcient to accommodate the implant without undue force or
distortion, yet not so extensive that it creates
unnecessary trauma or potential spaces that
might contribute to complications such as
seroma formation.
3. The use of two-point screw xation for immobilizing implants is a widely accepted prac-
tice. This technique provides stable
positioning of the implants, reducing the risk
of postoperative displacement or rotation,
which are critical for both the short-term
recovery and the long-term success of the
augmentation procedure.
4. Maintaining a clean operative eld and ensuring effective bleeding control are crucial in
preventing postoperative infections. Infection
remains one of the most signicant complications in implant surgery and can jeopardize
the outcome. Strict adherence to aseptic techniques, careful hemostasis, and perhaps the
use of prophylactic antibiotics are standard
practices to mitigate this risk.
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21 Alloplastic Modication oftheMidface
21.6 Case Study
Case 1
A 25-year-old man was planned for the malar reduction and V-line surgery. But, he had depressed
paranasal area because of recessed pyriform aperture. Thus, paranasal augmentation is performed using silicon implants of 5 mm simultaneously with the malar reduction and V-line
surgery. At 2-month follow-up after surgery, the result was satisfactory for paranasal area to
give more convex appearance to midface (Fig.21.5).
213
de f
Fig. 21.5 Case 1. A 25-year-old man was performed
paranasal augmentation using silicon implants of
5 mm simultaneously with the malar reduction and
V-line surgery. At 2-month follow-up after surgery, the
result was satisfactory for paranasal area to give more
convex appearance to midface
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214
Case 2
A 26-year-old woman was planned for the suborbital area augmentation simultaneously with
the malar reduction surgery. The prole was at to concave on midface, thus looked older than
her age. The thickness of silicon implant used was 4mm. At 2-month follow-up after surgery,
the prole view was improved at to convex, and she was satised with the result (Fig.21.6).
abc
S. Park
def
Fig. 21.6 Case 2. A 26-year-old woman was planned
for the suborbital area augmentation simultaneously
with the malar reduction surgery. The thickness of sili-
con implant used was 4 mm. At 2 month follow-up
after surgery, the prole view was improved at to
convex and she was satised with the result
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21 Alloplastic Modication oftheMidface
215
21.7 Complications
andManagement
21.7.1 Infection
Infection risks are heightened in the presence of
a foreign body, such as an implant used in midface augmentation. This is attributed to the
reduced minimal infecting dose of bacteria like
Staphylococcus aureus, as demonstrated in animal models. The impaired bacterial clearance
around the implant exacerbates this risk. When
microorganisms linger on an implant’s surface,
they adhere through nonspecic physical forces
and eventually form biolms. These biolms,
consisting of bacteria clustered within an extracellular matrix, adhere to the implant and effectively shield the bacteria from the host’s
immune defenses and antibiotics. Due to the
resilience of these biolms, treating implantrelated infections with antibiotics alone often
proves ineffective. Consequently, the standard
management of such infections typically
involves the removal of the implant, coupled
with antibiotic therapy and diligent wound care.
This approach underscores the importance of
preventive measures and early intervention in
the case of suspected infection.
21.7.3 Migration ofImplant
This complication is relatively rare when a twopoint xation approach is applied to the implant.
However, migration can occur if the screws used
for xation become loosened, rendering the xation ineffective. Another contributing factor to
implant migration is excessively wide dissection
without adequate xation. If xation is not utilized, the dissection should be precisely tailored
to the implant’s dimensions to minimize the risk
of migration.
21.7.4 Asymmetry
Asymmetric contouring in facial implant surgeries is not classied as a complication but is often
considered a dissatisfactory outcome. It is, in
fact, the most frequent reason for subsequent
implant removal or repositioning procedures.
Therefore, surgeons must exercise considerable
care and precision in placing the implants symmetrically. To achieve this, it is recommended to
use direct visual assessment and palpation from
the surface of the skin to ensure symmetry before
proceeding with the nal immobilization of the
implants using screws.
21.7.2 Sensory Disturbance
Sensory disturbance following alloplastic midface augmentation often results from the compression of the infraorbital nerve by the inserted
implant. Persistent symptoms of paresthesia
beyond 1day warrant serious consideration for
immediate removal of the implant to avert permanent nerve damage. This issue is most likely due
to the mobilization of the implant after soft tissue
closure. Therefore, careful visualization of the
infraorbital nerve both before and after implant
placement, coupled with secure xation using
screws, is crucial in preventing such sensory
disturbances.
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21.8 Discussion
The use of alloplastic implants for facial skeletal
contour restoration and improvement dates back
to the 1960s and 1970s. During this period, surgeons began employing materials like Silastic
sponges and solid polyethylene to reconstruct
post-traumatic, post-ablative, and congenital
defects. In the subsequent decades, particularly
the 1970s and 1980s, the new era began with the
potential of using alloplastic materials for aesthetic facial enhancement. Surgeons developed
techniques utilizing remote incisions to place
biocompatible materials under well-vascularized
216
S. Park
soft tissues, thus reliably altering the contours of
the facial skeleton.
The primary materials used for skeletal augmentation of the midface include silicone and
porous polyethylene. Silicone implants offer several advantages: they are easy to sterilize (by
steam or irradiation), can be shaped with scissors
or a scalpel, and can be secured with screws or
sutures. Clinically, silicone implants are welltolerated with no known allergic reactions. Their
smooth surface prevents soft tissue ingrowth,
facilitating easy removal if necessary. However,
disadvantages of silicone implants include the
potential for underlying bone resorption, the risk
of migration if not adequately xed, and the possibility of visibility of their brous capsule in
cases of thin soft tissue coverage.
Polyethylene, a simple carbon chain polymer
of ethylene monomer, is used in facial implants
with a porosity ranging between 125 and 250μm.
This porosity allows for brous tissue integration
into the implant’s surface. The advantages of this
integration include reduced implant migration
and less likelihood of eroding the underlying
bone. The porous nature also provides some exibility and adaptability to the implant. However,
these features come with drawbacks: the soft tissue ingrowth makes removal of the implant more
challenging and infection more vulnerable.
21.8.1 Hard Implant Versus Soft
Tissue Augmentation
Midfacial augmentation is often necessitated by
either soft tissue or skeletal deciencies, each
requiring a tailored approach. For issues stemming from soft tissue, techniques such as autogenous fat grafting or the use of various soft tissue
llers are effective. These methods address volume loss typically associated with aging, like
senile atrophy or sagging. Fat injection can easily
restore cheek volume. However, these techniques
have limitations, particularly when addressing
skeletal issues, due to restricted volume capacity
and resorption over time.
On the other hand, skeletal augmentation
using alloplastic implants offers a more predict-
able and lasting solution for enhancing the contours of a hypoplastic midfacial skeleton. While
bony resorption underneath the implant can
occur, its impact is generally minor in the midface compared to areas like the chin. While soft
tissue augmentation is useful for addressing volume decits due to soft tissue problems, alloplastic implants are more suited for providing
structural enhancement and addressing skeletal
insufciencies in the midface.
21.8.2 Host-Implant Interaction
Autogenous bone grafts, despite their long history of use, are characterized by varying degrees
of remodeling post-revascularization, leading to
changes in volume and shape. This unpredictability in the nal shape and volume makes them
less suitable for aesthetic midface augmentation
purposes, where precise outcomes are often
desired.
For skeletal augmentation of the midface, the
biocompatibility of the implant material is paramount. There should be an acceptable interaction
between the implant material and the host tissue.
Alloplastic implants, which are typically not broken down enzymatically by the host, maintain
their volume and shape over time. The body’s
response to these implants involves forming a
brous capsule around them, effectively isolating
the implant from the surrounding tissues.
The surface characteristics of the implant are
crucial in determining the nature of this encapsulation. Smooth-surfaced implants tend to result in
a smooth-walled capsule. In contrast, porous
implants allow for varying degrees of soft tissue
integration, leading to a capsule that is less dense
and less well-dened. This difference in capsule
formation can inuence the long-term stability
and integration of the implant, as well as its interaction with the surrounding tissue.
21.8.3 Immobilization
For facial implants, ensuring proper immobilization is crucial. Many surgeons opt to stabilize
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21 Alloplastic Modication oftheMidface
217
the implant’s position by suturing it to the surrounding soft tissues or using temporary transcutaneous pullout sutures. However, for midface
augmentation, screw xation of the implant to
the underlying skeleton is highly recommended.
This method of xation effectively prevents any
movement of the implant and ensures its close
adaptation to the bone surface.
The benets of screw xation are twofold.
Firstly, it eliminates the possibility of implant
movement, which is essential for maintaining the
desired aesthetic outcome and ensuring the stability of the implant. Secondly, screw xation
helps to eliminate any gaps between the implant
and the native skeleton. These gaps can lead to an
unintended increase in augmentation and serve as
potential spaces for the formation of hematoma
or seroma, both of which can complicate the
postoperative course.
Implant failure due to breakage or tearing of
the implant should be meticulously avoided while
using screw. This can be achieved through direct
visualization during the surgical procedure,
ensuring the implant is handled and positioned
correctly without undue stress or distortion. The
careful handling and secure xation of implants
are key steps in achieving successful outcomes in
facial augmentation surgeries.
References
1. Yaremchuk MJ. Skeletal augmentation. In: Neligan
PC, editor. Plastic surgery, vol. 2. 3rd ed. Seattle:
Elsevier Saunders; 2012. p.339.
2. Yaremchuk MJ, Israeli D. Paranasal implants –
correct midface concavity. Plast Reconstr Surg.
1998;102:1676–84.
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Secondary Zygoma Reduction
JihyuckLee
22
22.1 Pearls
1. The etiology of unfavorable results after
reduction malarplasty is classied into ve
categories: undercorrection of zygoma arch,
undercorrection of zygoma body, undercorrection of zygoma arch and body, zygoma
asymmetry, and zygoma malposition.
2. Sufcient medial displacement of the zygoma
complex is necessary for adequate reduction
of midfacial width. Appropriate posterior
repositioning of the zygoma complex is necessary to reduce the malar protrusion in
oblique view. Assessment of undercorrection
or necessity of reoperation should be evaluated in terms of facial width and malar
projection.
3. Although greenstick fracture of arch without
xation is easy and convenient, the result is
difcult to control accurately, and the position
of arch is unstable. Instability of arch may
induce asymmetry and relapse.
4. Inappropriate xation of zygoma complex in
reduction malarplasty can lead to zygoma
malposition and cheek ptosis. Rigid xation
with sufcient and healthy bony contact is
critical in secondary operation.
J. Lee (*)
Center for Facial Bone Surgery, Department of
Plastic Surgery, ID Hospital, Seoul, South Korea
e-mail: face@idhospital.com
5. Intraoral approach and minimal procedure is
still the rst choice for secondary operation
because the patients don’t want coronal scar
or big surgery.
6. Conservative procedure is recommended
when the amount of resection was large in the
rst surgery or bony gap is expected.
22.2 Introduction
Reduction malarplasty is a popular aesthetic surgery for contouring wide midface and prominent
malar area [1–9]. Some patients complain the
postoperative results and want to revise the malar
contour. The case of secondary reduction malarplasty grows up in Far East Asia. We analyzed the
etiology of unfavorable results and performed secondary reduction malarplasty for correcting the
problems of the previous surgery. The major complaint after a primary reduction malarplasty is
classied into ve categories: undercorrection of
zygoma arch, undercorrection of zygoma body,
undercorrection of zygoma arch and body, zygoma
asymmetry, and zygoma malposition [10–14].
Although greenstick fracture of arch with no
xation is easy and convenient, the result is difcult to control accurately, and the position of
arch is unstable. Instability of arch may induce
asymmetry and relapse. Recently, minimally
invasive zygomatic reduction without xation is
one of the major sources of instability and relapse
[11, 12, 14].
© 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_22
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219
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J. Lee
Inadequate osteotomy of the body is the most
frequent source of undercorrection. If placed too
low, the remaining body and orbital rim may cause
zygomatic prominence. Improper position after
osteotomy is the second frequent source of undercorrection. Thus, during the operation, check the
nal position of zygomatic body before xation,
and make sure that reduction is sufcient.
Unsecure xation may result drifting of body laterally and inferiorly due to muscle pull. Insufcient
resection of zygomatic body is quite common
when surgeon only use the osteotomy instead of
ostectomy. In patient assessment, amount of bony
resection in zygomatic body is critical and usually
necessary in Asian patients [2, 3, 8, 12–14].
22.3 Patient Assessment
The midfacial and malar morphology of the
patient is evaluated with clinical examination and
radiologic images. The shape and position of
zygoma is analyzed using simple radiography
and three-dimensional computed tomography.
The morphologic evaluation includes the degree
of zygomatic prominence, the amount midfacial
width, and the position of zygoma complex.
According to the prominent degree and portion,
the surgical plan was set up. The surgical plan
consists of the amount of body resection, the
amount of arch impaction, and the direction of
repositioning [2, 12, 13, 14].
22.4 Surgical Technique
The authors approached the body of zygoma
through an intraoral incision and the arch
through a 1-cm-long vertical incision within the
sideburns. The periosteum on the zygoma was
dissected and the scar tissue was trimmed. Also
we removed the wires, plates, and screws which
used in previous surgery. The scar tissue interposed between the previous osteotomy and
shaving site was removed. An inverted L-shaped
osteotomy and a vertical linear osteotomy were
applied to zygomatic body and arch, respectively. The previous osteotomy line was
trimmed, and the secure bone-to-bone contact
was made. The osteotomized zygomatic complex then was brought into the desired position
based on the surgical plan desired from preoperative analysis. With the zygoma in the desired
position, it is stabilized with plates and screws
at the body and arch of zygoma. The junction
between the anterior and posterior parts of the
separated zygomatic arch is xed with a midplate and screws. Bending midplate was prefabricated for relaxing the residual strength. On the
anterior side of the maxilla, the xation was performed with double-bridged plate for enhancing
the stiffness. With the double- bridged midplate
and the prebending midplate, we can achieve
the enhanced connection strength and improve
the stability of the repositioned zygoma
(Fig.22.1).
Fig. 22.1 Adequate bone contact and rigid xation. (Left) Applying a double-bridged midplate to zygoma body.
(Right) Applying a prebending midplate to zygoma arch
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