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BONE GRAFTING TO FACILITATE
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DENTAL IMPLANT PLACEMENT
George R. Deeb, Fahad M. Alsaad
CHAPTER 50
1. Which branchial arch are the maxilla and mandible derived from, and what type of
ossification do they undergo?
Both the maxilla and the mandible are derived from the first branchial arch, which is derived from the
neural crest ectomesenchyme. Craniofacial bone development is preceded by formation of cartilaginous
and membranous precursors that give rise to the neurocranium and viscerocranium. The maxilla and
mandible form by intramembranous ossification of the membranous viscerocranium. Maxillary ossification begins at the infraorbital foramen, and mandibular ossification begins at the mental foramen.
2. What is the basic histology of bone tissue and the cells within it?
Osteoprogenitor cells are the precursor to the bone matrix forming osteoblasts. They are located on the
endosteal surface of trabecular bone and periosteal surface of cortical bone. Once mature, osteoblasts
secrete type I collagen as well as other matrix proteins forming immature bone known as osteoid, which
subsequently mineralizes up to two-thirds of the bone matrix. These osteoblasts are called osteocytes.
As they become trapped with the matrix they form and are considered to be at the terminus of their
differentiation. They communicate with each other and the surface with an extensive canalicular network.
Osteoclasts are responsible for bone resorption and are derived from bone marrow monocytemacrophage precursor cells. The resorption process forms Howship’s lacunae where the osteoclasts
are housed.
3. Can you describe the difference between cortical and trabecular bone?
Cortical bone is made of dense, compact bone containing a series of osteons known as the Haversian
system, which is the functional unit of compact bone. Haversian canals lie within the osteons and contain vasculature. Biochemical communication between osteons occurs via Volkmann’s canals.
The functional unit of trabecular bone is the trabecular packets, which like the Haversian system
is formed of concentric lamellae of bone matrix. Turnover of trabecular bone is much higher than
cortical bone, and it is involved in mineral metabolism.
4. Can you describe primary bone healing?
Primary bone healing implies direct bone contact or a gap of less than 1 mm. Healing occurs in the
same process of bone turnover, by direct remodeling of the Haversian system. Osteoclasts work to
create a cutting cone, resorbing edges of the fracture, and osteoblasts follow and secrete osteoid for
future mineralization.
5. What are the three phases of secondary bone healing?
The primary phases of secondary bone healing are:
1. Inflammatory phase: Bleeding at the fracture edges forms a hematoma, which turns into
granulation tissue.
2. Repair phase: Inflammatory cells and fibroblasts invade the tissue. These cells cause the
recruitment of osteoblasts and provide a scaffold for vascular ingrowth. Osteoblasts lay down
osteoid and form a soft callus that eventually ossifies, forming woven bone.
3. Remodeling phase: This phase occurs over the next months to a year and restores bone to its
original shape and strength, by converting the woven bone to lamellar bone.
6. How do cortical bone grafts heal?
Block bone grafts heal by creeping substitution, a process similar to primary bone healing.
7. Do cortical bone grafts undergo complete resorption and replacement?
No, cortical block grafts are never completely resorbed and replaced by new bone. The nonvascular-
ized cortical bone block remains as necrotic centers with the newly formed bone.
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About 17% of resorption of the mandibular block autograft when combined with particulate autoand xenografts was noted on human studies, and an average of 5.0 mm of vertical height was gained
in ridge augmentation procedures. Maintenance of the vitality of autografts is achieved by revascularization, which protects against graft infection and necrosis.
8. Can you describe the healing of autogenous cancellous bone grafts?
Autogenous marrow contains both osteocompetent marrow stem cells as well as osteoblasts. These
cells remain viable through plasmatic diffusion. During the first week of healing, platelets release
an array of growth factors that promote angiogenesis and regeneration. During weeks 2 through 8,
the graft is revascularized by capillary ingrowth, and the osteoblasts begin to synthesize osteoid.
Remodeling is initiated by osteoclasts, which are stimulated by growth factors released during osteoid
formation. After 6 months of healing, 90% of the graft is matured.
9. What are the bone density categories and locations in the maxilla and mandible?
• D1: Dense cortical bone in the anterior mandible and in the posterior mandible
• D2: Dense to porous cortical bone in the anterior mandible and surrounding; dense trabecular bone
in the posterior mandible and anterior maxilla
• D3: Thin porous cortical bone in the anterior maxilla surrounding; fine trabecular bone and posterior
maxilla
• D4: Fine trabecular bone in posterior maxilla
10. How are alveolar ridge deficiencies classified according to Seibert’s
nomenclature?
• Class 1: Horizontal tissue loss with normal ridge height
• Class 2: Vertical tissue loss with normal ridge height.
• Class 3: Combined horizontal and vertical bone loss.
11. Which type of defect (vertical or horizontal) is more challenging to reconstruct?
Vertical alveolar bone loss is more challenging to reconstruct than horizontal bone loss.
12. What is another classification scheme for describing alveolar defects?
Defect classification can be described by the number of walls remaining. For example, an intact
extraction socket has five walls. When the buccal plate is missing, a defect has four walls
remaining. The more walls missing, the more difficult is the reconstruction. Total vertical bone loss
has only one wall remaining, which is the apical wall, and therefore is the most challenging to
reconstruct.
13. What is an osteogenic graft?
A graft that transfers osteocompetent cells to begin the bone-forming process. These cells along
with the osteocompetent cells at the defect site form new bone. Autogenous bone grafts are the only
osteogenic grafts and considered the gold standard in bone grafting.
14. What is an osteoinductive graft?
Osteoinductive grafts begin bone formation by stimulating host mesenchymal cells to differentiate.
This process occurs through the transfer of proteins in the graft. These proteins begin a signaling
cascade for the host to form bone.
15. What is an osteoconductive graft?
Osteoconductive grafts provide scaffolding for the host to form bone. These grafts do not contain
proteins or cells and therefore do not biologically influence the host.
16. What are the classifications of bone grafts based upon their source?
Autograft Graft taken from the same host
Allograft Graft taken from a genetically similar donor, as in cadaveric graft
Xenograft Graft taken from a genetically dissimilar donor, most commonly bovine or
Synthetic graft Graft not taken from a living donor
17. What are the most common bone graft materials based on their source?
Autograft Cadaver cortical/cancellous bone, FDBA (freeze-dried bone allograft),
porcine source
No cellular or protein products in this graft
DFDBA (decalcified freeze-dried bone allograft)
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Xenograft Bio-Oss, Endobon, coralline HA, red algae
Alloplast (synthetic) Calcium sulfate, calcium phosphate, bioactive glass, hydroxyapatite, porous
18. What are the most common bone grafts based upon their osseous induction
potential?
Osteogenic Autograft
Osteoinductive BMP (bone morphogenic protein), DFDBA (decalcified freeze-dried bone allograft),
Osteoconductive Bio-Oss, Endobon, calcium phosphate, calcium sulfate, collagen,
19. What are the most common factor-based materials?
Platelet-rich plasma (PRP), bone morphogenic proteins (BMPs), platelet-derived growth factor (PDGF).
20. What are the most common sites for harvesting regional bone autografts?
• Mandibular symphysis
• Mandibular ramus and body
• Mandibular coronoid process
• Zygomatic buttress
21. What is the harvest of a mandibular symphysis graft?
Either a sulcular of vestibular incision is made. Sulcular incisions will result in recession in some
patients with a thin periodontium, or in the presence of crown and bridge work. Distal oblique releases
are made distal to the second premolar. The vestibular incision is similar to that for a genioplasty. The
vestibular incision will bleed more due to the mentalis and gives slightly less access than the sulcular.
The vestibular incision should be closed in two layers to avoid chin ptosis. The vestibular incision is
associated with wound dehiscence, scar band formation, and pain more often. The sulcular incision is
closed in an interrupted fashion through the papilla.
The superior osteotomy line should be 5 mm below the root apices. All portions of the osteotomy
should completely penetrate the labial plate. The osteotomy is completed using round or fissure burs,
and thin chisels. The dimensions of the corticocancellous blocks are usually adequate for reconstructing the width of three teeth, or up to 6 mm in horizontal and vertical dimensions.
22. What is the harvest of a mandibular ramus graft?
The incision to access the mandibular ramus for grafting begins on the edentulous crest distal to the
teeth and includes mesial and distal oblique releases as necessary for access. The superior osteotomy
is made 5 mm medial to the external oblique ridge. The vertical osteotomies are made mesially and
distally according to bone grafting needs and 10 to 12 mm in vertical height. The inferior osteotomy
scores the lateral cortex at the height desired. Using a thin chisel, the bone is outfractured. In 10% to
12% of patients the inferior alveolar nerve will be visible. The wound is closed in a running or interrupted fashion.
23. Can you describe the harvest of mandibular coronoid bone?
An incision over the ascending ramus should be made beginning at the level of the occlusal table of
the mandibular molar and extended to the midpoint of the ramus. Complete striping of the temporalis is required. The coronoid is grasped with a forceps and a reciprocating saw used to amputate
it inferiorly to the forceps. The lingula is located 10 mm below the sigmoid notch, so the osteotomy
should not be made more than 5 mm inferior to the notch. The coronoid process has sufficient bone
to augment one or two teeth width and 3 to 4 mm in a horizontal or vertical direction. The wound is
closed in a running or interrupted fashion.
24. What is the procedure for harvesting bone from the zygomatic buttress?
Access to the zygomatic buttress is gained by making a vestibular incision from the canine distally to
the first molar area. Superolateral dissection is carried out. Four osteotomies, two vertical and
two horizontal, are outlined and completed with a fissure bur. The bone is removed with a chisel.
The limiting anatomic barriers are the sinus inferiorly and the infraorbital nerve superiorly.
The wound is closed in a running or interrupted fashion.
nickel titanium
DBM (demineralized bone matrix)
FDBA, glass ionomers, HA (hydroxyapatite), (NiTi) porous
nickel titanium
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25. Can you describe the bone resorption in an alveolus after extraction?
The thin cortical buccal plate of an extraction socket is predisposed to a more rapid post-extraction
resorption when compared to other walls of the socket. This explains the decrease in ridge width
compared to height. Up to 50% of the buccal ridge width and 20% of the ridge height may resorb
within the first 6 months after extraction.
26. What are some of the surgical requirements and principals necessary for block
graft success?
For a more predictable successful outcome in block grafts, it is critical to insure stability and contact
with the host recipient bed. Stabilization may be achieved with fixation screws or immediate placement of the dental implant into the graft. Other techniques that can improve success rate are recipient
bed preparation, i.e., decorticating holes to expose the cancellous marrow and improve revascularization of the graft and subsequently its integration. Corticocancellous grafts are favored over cortical
block grafts due to their faster revascularization. Graft resorption can be minimized with the use of
barrier membranes.
27. What procedure will help minimize bone resorption after extraction?
Socket preservation. Most studies support the concept of grafting an extraction site to minimize bone
resorption. Nonetheless it is an additional procedure that adds more cost and a potential for complications. Therefore the clinician should be selective of when to graft, as it has been shown in animal
and human studies that ungrafted extraction sites with completely intact bony walls heal without
significant defects on their own.
Sites where the buccal cortical bone is thin and resorption is anticipated, such as the anterior
maxilla, socket grafting is recommended. The use of a barrier membrane is also advocated to prevent
fibrous encapsulation of the graft.
28. What are guided bone regeneration (GBR) and guided tissue regeneration (GTR)?
GBR refers to the formation of bone alone, while GTR refers to the regeneration of the supporting
apparatus including cementum, periodontal ligament, and alveolar bone. GTR and GBR use barrier
membranes for space maintenance over a defect promoting ingrowth of osteogenic cells and
preventing ingrowth of overlying soft tissues into the wound.
29. How much vertical ridge height can be augmented with the use of a barrier
membrane?
Studies have shown that up to 4.0 mm of bone can be grafted vertically, without the use of grafting
materials, using titanium-reinforced membranes. Additional vertical height can be achieved using
grafting materials. Studies have shown an implant success rate of 97.5% in vertically grafted bone,
which is comparable to implant success placed in native or horizontal bone.
30. Describe some of the nonresorbable membrane options for bone grafting.
Expanded polytetrafluoroethylene (ePTFE) is the most common type of nonresorbable membrane
used. Subtypes of it include porous ePTFE, which allows tissue adherence to the membrane for
stabilization, high-density ePTFE that prevents tissue ingrowth, and titanium reinforced for better space
maintenance in larger defects. Plain titanium has also been used for ridge augmentation procedures.
31. What are the advantages of use of titanium mesh in bone grafting in preparation
for implant placement?
The rigidity of titanium mesh helps maintain the space where bone proliferation is intended and
prevents collapse of the soft tissue envelope.
32. What are the types of bioabsorbable barriers available for intraoral bone grafting?
There are two main types of bioabsorbable membranes, which are natural or synthetic. Natural
membranes are mostly derived from collagen of an animal origin, and they resorb by enzymatic
digestion. Synthetic membranes are polymer products such as polylactic and polyglycolic acid.
Those degrade by hydrolysis process.
33. What are the approaches to sinus augmentation?
There are two main techniques to consider when the maxillary sinus requires an augmentation. A
conservative approach is performed through a crestal osteotomy using the sequenced implant drills,
leaving a thin interface of bone at the sinus floor that will tap into the sinus cavity with osteotomes
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designed for that purpose, while care is taken to avoid tears to the schneiderian sinus membrane.
Particulate bone graft material may be packed into the prepped site. About 3 to 5 mm of sinus floor
elevation is gained with this method.
When more sinus elevation is desired, a more invasive approach may be considered. This
involves a modification of the Caldwell-Luc procedure, where a window at the lateral sinus wall is
made, without perforation into the schneiderian membrane, creating a trapdoor access. The membrane is carefully dissected and lifted from the floor. The bony segment of the sinus window is tucked
in as part of the graft, and the reminder of the space between the sinus and its membrane is filled
with a graft material. Resorbable membrane is placed to cover the lateral window, and the tissue flap
is closed primarily.
The choice between one method over the other depends on the length of the implant, amount of
preoperative crestal bone, and the timing of implant placement, whether at the time of sinus augmentation or as a secondary stage.
34. What materials are used for sinus bone grafting?
There are numerous grafting materials that can be used in sinus augmentation, all of which show
high success rates. These materials include autogenous grafts, xenografts, hydroxyapatite, particulate
allografts, and BMP-2. In other studies, tenting of the maxillary sinus membrane with the implant fixture without placement of a graft resulted in bone formation and similar success. It is recommended
to place a resorbable barrier membrane over the sinus window to protect and contain the graft.
35. Are there any contraindications to sinus floor augmentation?
Clinical or radiographic evidence of sinusitis or any other sinus pathology warrants a referral to an
otolaryngologist evaluation and management before considering augmentation procedure at the
maxillary sinus.
36. What is a ridge-splitting procedure? What is a two-stage ridge-splitting
procedure?
A ridge-splitting procedure involves making a longitudinal crestal osteotomy using chisels or a piezo-
tome to separate the buccal and lingual cortices, thus widening the ridge and gaining horizontal width.
An interpositional graft may be placed at the intercortical gap to provide stability, along with primary
closure.
A modification to this technique involves a two-stage procedure. The initial surgery is aimed
toward making a horizontal apical and two vertical osteotomies on the buccal cortex after a full
thickness mucoperiosteal flap. The osteotomies outline the buccal segment to be split in stage two.
One month later, the second surgery is performed where a split thickness flap is reflected to maintain
blood supply to the previously osteotomized segment, which can now be split to widen the ridge.
At this stage implants may be placed or an interpositional graft. The rationale for the two-staged
approach is to have predictable buccal segment size and prevent unfavorable fractures.
37. Can you describe the tunneling technique used for horizontal lateral ridge
augmentation?
Alveolar ridges with thin crestal bone usually have a wider base and are indicated for this tunneling
technique. A vertical incision is made anterior to the site to be augmented. While being cognizant of
the mental nerve in mandibular grafts, a subperiosteal pocket is made. Soft tissue is only reflected
from the thin portion to receive the graft, where the wider basal bone will act as a shelf to hold the
particulate graft, which is packed into the pocket. Finally the incision is closed primarily with sutures.
38. What are the different methods of managing a vertically deficient posterior mandibular ridge?
• Inferior alveolar nerve lateralization
• GBR and onlay grafts
• Use of short implants
• Interpositional grafts
39. Can you describe the vertical ridge augmentation technique with an interpositional graft?
After local anesthesia is administered, a horizontal vestibular incision is made about 15 mm apical to
the crest, while being cognizant of the mental nerve. Then a vertical release incision is made in the
interdental space one tooth anterior to the planned osteotomy. A buccal flap may be reflected while
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preserving the crestal and lingual periosteal attachment to the crestal alveolus to maintain its blood
supply. A piezotome is used to complete horizontal and vertical osteotomies, carefully avoiding perforating the lingual soft tissue. Vertical osteotomies must be slightly diverging at the crest to prevent
undercut locking of the segment. Next, the segment is mobilized vertically to the extent allowed by the
lingual tissue and fixated with small bone plate. Finally a particulate bone graft material is packed into
the created gap. The flap then is closed without tension.
40. How much vertical bone height may be gained from an interpositional graft
technique?
The lingual tissue attachment allows about 4 to 5 mm of crestal segment elevation. In severely
deficient ridges where the osteotomized crestal segment is close to the floor of the mouth, the laxity
of the lingual tissue may allow for up to 7 to 8 mm of elevation.
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Dent Pract 12(Suppl 3):149–160, 2012.
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implants: a new surgical technique in maxillary sinus floor augmentation, Periodontology 2000 47(1):193–205, 2008.
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Misch C: Contemporary implant dentistry, ed 3, St Louis, MO, 2007, Mosby.
Peterson L: Peterson’s principles of oral and maxillofacial surgery, ed 2, Hamilton, Ontario, 2004, BC Decker. eBook, p 1055.
Proussaefs P, Lozada J: The use of intraorally harvested autogenous block grafts for vertical alveolar ridge augmentation: a
human study, Int J Periodont Restorat Dent 25(4):351–363, 2005.
Rachana CN, Sridhar, Rangan AV, Rajani V: Horizontal ridge augmentation using a combination approach, J Ind Soc
Periodontol 16(3):446–450, 2012.
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Sadler TW: Langman’s medical embryology, ed 12, Baltimore, MD, 2012, Lippincott Williams & Wilkins. eBook, p 264.
Seibert JS: Reconstruction of deformed partially edentulous ridges, using full thickness onlay grafts. part I. technique and
wound healing, Comp Contin Educ Dent 4:437–453, 1983.
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February 01, 2013.
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Din Lam
CHAPTER 51
1. What is the principle of the reconstructive ladder?
Mathes and Nahai originally introduced the concept of the reconstructive ladder in 1982 to provide
a systematic way of thinking about wound closure. The “ladder” included primary closure at the
bottom rung and ascended through increasingly complex reconstructive means such as skin grafts
or local flaps toward microvascular free tissue transfer at the top. It is an important concept designed
to improve predictability of wound coverage. In the head and neck reconstruction, however, rungs of
the ladder are often skipped to achieve more ideal restoration of form and function. For instance, a
composite mandibular defect may be closed using a regional flap such as the pectoralis major that
would be lower on the reconstructive ladder than a free flap. However, given the widely recognized
predictability of free flaps, an osteocutaneous free tissue transfer may be selected as a more ideal
reconstruction.
2. How does a skin graft heal?
Skin graft healing require three phrases. During the first 48 hours, the process of plasmatic imbibition
allows the graft to survive the immediate post-graft period before circulation is established. Imbibition is a process that allows nutritive materials to diffuse from the host bed to the skin graft. After
48 hours, anastomotic connections are established between host and graft vessels (inosculation). At
the same time, angiogenesis occurs in the skin graft.
3. What is the difference between full-thickness skin grafts (FTSGs)
and split-thickness skin grafts (STSGs)?
STSGs are 0.30 to 0.45 mm thick. The skin is sectioned below the papillary dermis, so it will only
contain epidermis and a portion of the upper reticular dermis. Because the skin adnexa (hair follicles
and associated sebaceous glands, eccrine and apocrine sweat glands) originate in the midreticular
dermis or in the subcutaneous fat layer, they are generally not included in STSGs.
In FTSGs, the dermis is not split. The plane of cleavage is designed to separate the subcutaneous
fat from the dermis. The actual thickness of an FTSG is extremely variable and depends on the location on the donor site and the sex, age, and health of the patient.
The eyelid and supraclavicular and postauricular skin are the thinnest on the body, whereas the
palms, soles, and trunk are the thickest. Women have thinner skin. The dermis is very thin in children;
it increases until age 50, and then it atrophies. Conditions such as malnutrition, chronic steroid
therapy, and insulin-dependent diabetes mellitus also affect dermal thickness.
4. What are primary and secondary contractions?
Primary contraction refers to the immediate elastic recoil of the graft as it is harvested. Secondary
contraction occurs during the healing process of the graft and is clinically more significant. The less
dermis, the more the graft will contract secondarily.
5. What percentage of contraction can be expected from STSG and FTSG?
A full-thickness graft loses about 40% of its original area, and a thin, split-thickness graft contracts by
approximately 10%. In contrast, STSG has significantly more secondary contraction.
6. When are meshed grafts used?
Meshed grafts are useful when insufficient donor skin is available, when a highly convoluted area
must be covered, when the recipient bed is less than optimal, or when moderate drainage is anticipated. Graft meshing is usually performed in 1:1.5 or 1:2 ratios.
7. What are the best types of dressings for a donor site?
Donor site dressing for skin grafts can be categorized into four types: open, semiopen, semiocclu-
sive, and occlusive. Open technique is associated with prolonged healing time and increased pain.
Semiopen technique utilizes Xeroform gauze to be place over the harvesting site and secured with
regular wound dressing. Semiocclusive dressing, such as Op-site and Tegaderm, are bacteria- and
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liquid-impermeable but permeable to moisture. They promote faster and less painful healing but are
more labor intensive. Fluid or exudates tend to collect under the dressings and need to be drained
frequently. Occlusive dressing, such as Duoderm, enhances the rate of epithelialization and collagen
synthesis and reduces the bacteria count by decreasing the pH of the exudate. Furthermore, because
it does not adhere to the bed, it does not cause irritation or pain.
8. What are the advantages of using local flaps in the head and neck?
• Similar color and texture of the skin for the site of the defect.
• Donor sites frequently can be closed directly.
• Little or minimal scar contracture.
9. What factors most affect aesthetics and function following reconstruction with
local flaps?
Using physical characteristics of tissue can lead to better functional and aesthetic results after
reconstruction with local flaps. Such characteristics include integration of relaxed skin tension
lines, taking into consideration the cosmetic units of the face, and better use of the physical
properties of the skin.
10. Can you describe the various types of local flaps?
• Random flap: Blood supply is from subdermal plexus.
• Axial flap: Blood supply is from a segmental artery that runs the length of the flap.
• Advancement flap: The skin adjacent to the defect is undermined and advanced.
• Rotation flap: A flap is rotated along an arc into the defect.
• Transposition flap: A flap is passed over an incomplete bridge of the skin.
• Interpolated flap: A flap is passed over or under a complete bridge of skin, which separates the flap
from the defect (paramedian flap).
11. What is stress relaxation?
As a constant load is applied to the skin causing it to stretch, the load required to maintain this stretch
will decrease.
12. What is tissue creep?
As a sudden load is applied to the skin and kept constant, the amount of extension of the skin will
increase as more time is applied.
13. Where should incision lines for local flaps and donor area fall?
Lines of minimal relaxed tension. The skin tension is at right angles to these lines.
14. In the design of a Z-plasty, what angles yield what percentage of gain in length?
• 30° will yield 25% gain in length.
• 45° will yield 50%.
• 60° will yield 75%.
15. What are the indications for a Z-plasty?
• To realign scars within the resting skin tension lines
• To adjust contours by reorienting the tissue
• To lengthen any linear scar contractures
• To disperse scars for cosmetic adjustments
16. What are Burrow’s triangles?
This is excess skin that one will find at the base of an advancement flap. This skin needs to be
excised to complete the flap.
17. In a rotation flap, what is the typical shape should the defect be excised? And
where is the line of greatest tension?
A triangle with the base as the shortest side is the typical defect repaired with a rotation flap. The line
of greatest tension extends from the pivot point of the flap to the edge of the defect nearest to where
the flap previously lay.
18. What are the causes of local flap failures in the head and neck?
• A small flap designed to fill a large defect
• Hematoma
• Compromised blood supply
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• Tension during closure
• Unfavorable flap design (length:width ratio > 3:1)
19. What are the most common regional flaps with their vascular supply?
See Table 51-1.
20. What is the most common complication related to a temporalis flap? And how
can it be prevented?
Temporal hollowing is commonly noticeable when the donor site is not properly reconstructed. A
temporalis flap can be divided into two pedicles: anterior and posterior pedicles. Most defects can
be repaired with only the anterior pedicle, where the posterior pedicle can be advanced anteriorly to
prevent temporal hollowing. Alternatively, an alloplastic implant can also be used to restore the donor
site defect.
21. How can one prevent vessel injury when harvesting a submental island flap?
To ensure safety of the submental island flap, a portion of anterior digastric muscle should be
harvested with the vascular paddle. Further precaution can be taken if incorporating a portion of
mylohyoid muscle with the vascular paddle. This modification helps to sandwich the vessel between
two muscle tissues.
22. Can a submental island flap be used in reconstructing an ablative defect from
malignant pathology?
The major concern of using a submental island flap in a malignant patient is related to incomplete
removal of lymphatic tissue in the Level IA region. Although Hayden et al. have reported a series of
reconstructive cases with submental island flap on patients with squamous cell carcinoma, the utility
of this flap in this patient population remains controversial. This flap, however, will be a great option
for the surgeon in treating malignant pathologies that carry a low metastatic rate to the neck, such as
adenoid cystic carcinoma and sarcoma.
Table 51-1. The Most Common Regional Flaps with Their Vascular Supply
FLAP DOMINANT BLOOD SUPPLY
Pectoralis major myocutaneous Thoracoacromial artery
Deltopectoral skin Perforators from internal mammary artery
Temporalis muscle Anterior and posterior deep temporal arteries
Temporoparietal fascia Superficial temporal artery
Paramedian flap Supratrochlear artery
Nasolabial flap Random flap or axial flap based on angular artery
Submental island flap Submental artery
Facial arterial myomucosal flap Branch of facial artery
Tongue flap Most common tongue flap is random flap. Axial
Palatal island flap Greater palatine artery
Platysma myocutaneous Submental branch of facial artery
Trapezius myocutaneous Transverse cervical artery
Latissimus dorsi myocutaneous Thoracodorsal artery
Sternocleidomastoid myocutaneous Branches of occipital and superior thyroid arteries
Trapezius flap Dorsal scapular artery
Supraclavicular flap Supraclavicular artery
Superior and lateral thoracic arteries contribute
flap design is based on dorsal-lingual branch of
lingual artery
CHAPTER 51 LOCAL AND REGIONAL FLAPS 461
https://t.me/medicina_free
23. When harvesting a pectoralis major myocutaneous flap, how much skin paddle
off the muscle can one incorporate?
Size and location of skin paddle depends on reconstructive needs. Typical skin paddle is harvested at
the infero-medial border of the pectoralis major muscle. The sixth costal cartilage serves as a landmark for the inferior border of the muscle. Skin overlying any portion of the muscle can be utilized,
and the larger the skin paddle, the more likehood the skin will survive due to the increased number of
myocutaneous perforators. Additional 3–5 cm length can be harvested beyond the inferior edge of the
pectoralis muscle as a random pattern flap.
24. When reconstructing a head and neck defect with a pedicled latissimus dorsi
myocutaneous (LDM) flap, how does one transfer this flap to the recipient site?
A pedicled LDM flap is not commonly used in head and neck reconstruction since the increasing
popularity of free flap. However, it remains an important flap for the reconstructive surgeon, especially
in the case of a patient with depleted neck vessels. A pedicled LDM flap is easy to harvest and
provides a large volume of tissue. Once the flap is raised, the pedicled LDM flap will be delivered to
the recipient site by creating a subcutaneous tunnel around the deltopectoral region or between the
pectoralis major and minor muscles.
25. For a palatal island flap, is it possible to harvest the entire palatal tissue based on
a single artery?
Yes. A rich anatomic network, called the trilaminar macronet, exists within the mucosa, submucosa,
and periosteum between the right and left greater palatine arteries. This dense network allows the
entire palatal tissue to be harvested based on single greater palatine artery.
26. What are the two variations of a facial arterial myomucosal (FAMM) flap?
A FAMM flap can be either a superiorly or inferiorly based flap, depending on the location of the
defect. A superiorly based FAMM flap is based on the retrograde flow of the facial artery and is used
to reconstruct a soft tissue defect found in the maxilla, palate, or floor of the nose. An inferiorly based
FAMM flap is based on the antegrade flow of the facial artery and is used to reconstruct a soft tissue
defect found in the floor of the mouth and lower jaw.
27. When performing a tongue flap, what determines whether it should be an
anteriorly or posteriorly based flap?
The location of the defect determines where a tongue flap is based. For defects of the soft palate,
retromolar region, and posterior buccal mucosa, a posteriorly based flap is used. Anterior-based
flaps are used for hard palate defects, defects of the anterior buccal mucosa, and anterior floor of
the mouth or lips.
28. How long before you can safely divide the pedicle when using a tongue flap to
repair oronasal communication?
Most tongue flaps used for oral cavity reconstruction require a two-stage procedure. The first stage
is to harvest and to insert the flap to the recipient sites. At this stage, the flap remains attached to the
donor site for its blood. After 10 to 14 days, a new blood supply to the recipient site is established, and
attachment to the donor site can be safely divided.
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