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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_4430_Библиотеки_им_академика_М_И_Перельмана
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posterior surface of the implant to be congruent with the anterior surface of the
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implant thereby avoiding gaps. Fig. 12.13 shows a mandible implant that was
improperly positioned or perhaps dislocated due to lack of fixation.
It is crucial to soften any transitions between the implant and the mandible,
particularly where the implant extends beyond the anterior mandibular border’s inferior edge. Any step-offs between the implant and the mandible in this
area may be visible in thin patients. Screw fixation of the implants allows scalpel
or mechanical burr final contouring with the implants in place. After hemostasis
as appropriate, the wound is irrigated (antibiotic irrigation is a rational adjunct
to decrease bacterial contamination in this operation performed through intraoral access). A suction drain with trocar travels through the skin and exits in the
postauricular area. The incision is closed in two layers with absorbable sutures.
Care is taken to evert the mucosal edges. An elastic tape dressing is used to help
apply the soft tissues to the implant and avoid hematoma formation. The suction drain usually remains until the next morning unless drainage persists.
Fig. 12.12 Screw xation applies the implant to the skeleton
and obliterates the gaps. (Gaps are equivalent to an increase in
augmentation.) (A) Sagittal view shows discrepancy in contour
between anterior surface of the mandible and posterior surface of
the implant resulting in gaps. (B) The upper screw is in place and
has xed and immobilized the implant to the skeleton. (C) The
lower screw has been placed. The posterior surface of the implant
is now congruent with the anterior surface of the mandible. The
skeleton and xed implant now reect the desired contour and
projection.
Operative technique
A B C
Fig. 12.13 CT scan demonstrates malpositioned mandible implants.
Improper implant position and postoperative implant movement
due to lack of xation may have contributed to poor outcome.
Video 12.1 demonstrates the placement of a mandible angle implant.
Patients are administered broad spectrum antibiotics (cephalosporins) intravenously immediately before the procedure. Oral antibiotics are administered
for 5 days postoperatively.
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Chapter 12 Mandible
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A liquid diet is prescribed for the first 3 days postoperatively and a soft diet
for the next 5 days. Frequent mouth washes are advised as well as very careful
tooth brushing.
Pterygomasseteric sling disruption and repair
Disruption of the pterygomasseteric sling causes the masseter muscle to retract.
Masseter retraction results in a soft tissue deficit where it had joined the pterygoid at the inferior border. The retracted muscle bulges just above the deficit
(Fig. 12.14). The resultant contour deformity can be improved. The extent of correction has depended on the chronicity of the disruption. The longer the duration of the muscle retraction, the greater the scarring causing less mobility.
11
Medial
pterygoid
Contracted
Masseter
Periosteal
tear
Periosteum
A B C
Fig. 12.14 Artist’s rendition of disruption of pterygomasseteric sling. (A) Sling intact. (B) Sling disrupted and mandible border exposed. (C)
Contraction of masseter results in bulge at mid-aspect of ramus.
masseter
Mandibular
implant
Repair can done through an internal or external approach. A subperiosteal
dissection allows identification of the retracted edge of the masseter muscle and
the inferior border of the mandible. Two or three figure-of-eight sutures purchase the inferior border of the muscle. The muscle is pulled down and sutured
to the drill holes made at the inferior border of the mandible (Fig. 12.15).
Fig. 12.15 The inferior border of the ramus and retracted edge of
the masseter has been identied through a facelift approach. The
retracted edge has been purchased with gure-of-eight sutures and
will be sewn to drill holes located at the border of the mandible.
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CLINICAL EXAMPLES
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Clinical examples are shown in Figs. 12.16 to 12.20.
Clinical examples
A
D
Fig. 12.16 A 30-year-old male actor with normal facial dimensions and class I dental occlusion desired more “strength” to his jaw and
requested chin augmentation. After evaluation, a mandible ramus and posterior body augmentation with the implants described in Fig. 12.6
was performed as well as a tertiary rhinoplasty. (A) Preoperative frontal view. (B) Postoperative frontal view. (C) Artist’s simulation of implant
surgery – frontal view. (D) Preoperative lateral view. (E) Postoperative lateral view. (F) Artist’s simulation of implant surgery – lateral view.
B
E
C
F
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Chapter 12 Mandible
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A
D
Fig. 12.17 A 21-year-old woman who had undergone orthodontic correction of her class II malocclusion desired improved nasal and
mandibular contour. Rhinoplasty and mandibular augmentation with mandibular ramus and body implants as well as an extended chin
implant were undertaken. (A) Preoperative frontal view. (B) Postoperative frontal view. (C) Artist’s simulation of implant surgery – frontal view.
(D) Preoperative lateral view. (E) Postoperative lateral view. (F) Artist’s simulation of implant surgery – lateral view.
B
E
C
F
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Clinical examples
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A
D
B
E
C
F
Fig. 12.18 A 35-year-old male had ve previous chin operations. He desired a very strong mandible. A silicone chin implant was removed.
A 9-mm porous polyethylene chin implant and a mandibular angle implant were placed. The chin pad was resuspended. (A) Preoperative
frontal view. (B) Preoperative lateral view. (C) Preoperative oblique view. (D) Postoperative frontal view. (E) Postoperative lateral view. (F)
Postoperative oblique view.
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Chapter 12 Mandible
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Fig. 12.19 A 30-year-old man with
Treacher–Collins syndrome underwent
advancement sliding genioplasty as an
adolescent. A 9-mm porous polyethylene
chin implant and mandibular implants were
placed. (A) Preoperative frontal view. (B)
Preoperative lateral view. (C) Preoperative
oblique view. (D) Postoperative frontal
view. (E) Postoperative lateral view. (F)
Postoperative oblique view.
A
B
D
E
C
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F
A B
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References
C
D
Fig. 12.20 A 24-year-old woman underwent chin and mandible augmentation. (A) Preoperative frontal view. (B) Postoperative frontal view.
(C) Preoperative oblique view. (D) Postoperative oblique view.
REFERENCES
1. Farkas LG, Hreczko TA, Katic MJ. Craniofacial norms in North American Caucasians from
birth (one year) to young adulthood. In: Farkas LG, editor. Anthropometry of the head and
face. 2nd ed. New York: Raven Press; 1994.
2. Bell WH, Proffit WR, Chase DL, Wickwire NA, Poultom DR. Mandibular deficiency. In: Bell
WH, Proffit WR, White RP, editors. Surgical correction of dentofacial deformities, vol. 1.
Philadelphia: Saunders; 1980.
3. Semergidis TG, Migliore SA, Sotereanos GC. Alloplatic augmentation of the mandibular angle.
J Oral Maxillofac Surg 1996;54(12):1417–23.
4. Terino EO. Alloplastic facial contouring: surgery of the fourth plane. Aesthetic Plast Surg
1992;16(3):195–212.
5. Terino EO. Unique mandibular implants, including lateral and posterior angle implants. Facial
Plast Surg Clin North Am 1994;2:311–28.
6. Whitaker LA. Aesthetic augmentation of the posterior mandible. Plast Reconstr Surg
1991;87(2):268–75.
7. Aiche AE. Mandibular angle implants. Aesthetic Plast Surg 1992;16(4):349–54.
8. Taylor CO, Teenier TJ. Evaluation and augmentation of the mandibular angle region. Facial
Plast Surg Clin North Am 1994;2(3):329–37.
9. Ramirez OM. Mandibular matrix implant system: a method to restore skeletal support to the
lower face. Plast Reconstr Surg 2000;106(1):176–89.
10. Yaremchuk MJ. Mandibular augmentation. Plast Reconstr Surg 2000;106(3):697–706.
11. Thomas MA, Yaremchuk MJ. Masseter muscle reattachment after mandibular angle surgery.
Aesthet Surg J 2009;29(6):473–6.
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Video 12.1 Mandible angle augmentation. This video demonstrates the placement of a
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porous polyethylene mandible angle implant immobilized with titanium screws.
178.e1
Chapter 13
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Rejuvenation of the aging face
and skeleton with implants
In his article “Anatomy and pathophysiology of facial aging”, Zimbler states,
“Facial aesthetics begin with the marriage of hard and soft tissue integration;
however, it is the changing balance of these elements that is the hallmark of the
aging process … A youthful face therefore represents a point in time when a
particular set of skeletal proportions are ideal for their soft tissue envelope.”
SOFT TISSUE AGING
Soft tissue ptosis secondary to gravity has long been considered the major
mechanism responsible for facial aging. There is no doubt that gravity and
ptosis are the main factors leading to facial aging.2 Lambros and others have
concluded that changes in volume of cheek fat, both loss and gain, rather than
ptosis account for an aged appearance.
ever, show that there are also many changes to the craniofacial skeleton as
patients age that contribute to the aging process.
The aging face typically shows the following changes: descent of the brow,
changes in contour of the upper eyelid, medialization of the lateral canthus,
lower eyelid descent, deflated infraorbital skin envelope, increased visibility of
the lid–cheek junction and nasojugal crease, increased prominence and depth
of the nasolabial fold, and increased prominence of the labiomandibular crease.
These signs of aging have been related to changes in skin and soft tissue.
In addressing soft tissue ptosis and volume changes, many facelifting techniques involve the removal of excess skin and also fat grafting and sculpturing. The main purpose of this chapter is to address the skeletal changes in the
face that contribute to aging. Other chapters discuss the techniques available to
address and reconstruct the facial skeleton for a more youthful appearance as a
sole procedure or in addition to other techniques.
3,4
Numerous anatomical studies, how-
1
FACIAL SKELETON AGING
In addition to soft tissue changes, it has been demonstrated that there is remodeling of the craniofacial skeleton with age,
the orbit.
which is the process of skeletal remodeling due to mechanical forces of soft tissue on bone.
factors and processes are the prior, proximate, extrinsic, and primary cause
of all adaptive, secondary responses of skeletal tissues and organs.”10 This
8,9
These will be discussed separately in the remainder of this chapter.
One of the theories behind the skeletal changes is mechanotransduction,
10
The functional matrix hypothesis states that “epigenetic, extra skeletal
5–7
for example, bony remodeling in
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