exploiting the anatomy of the temporal fossa. The use of temporalis to glide Yousif NJ, Mendelson BC 1995 Anatomy of the midface. Clin Plast Surg
the elevator down to below the arch is insightful. 22:227–40.
Gonçalves RC, Ravell DB, Ados A 2011 Effects of age and gender on upper Ziarah HA, Atkinson ME 1981 The surgical anatomy of the mandibular
airway, lower airway and upper lip growth. Braz Oral Res 25:241–7. distribution of the facial nerve. Br J Oral Surg 19:159–70.
Gosain AK, Yousif NJ, Madiedo G et al 1993 Surgical anatomy of the SMAS: An outline of how the mandibular branch of the facial nerve is at risk in all
a reinvestigation. Plast Reconstruct Surg 92:1254–63. incisions at the lower border of the mandible, in submandibular gland
excision, incision of space-occupying dental infections, and neck dissection.
Kwak HH, Park HD, Youn KH et al 2004 Branching patterns of the facial
A detailed knowledge of this structure is essential.
nerve and its communication with the auriculotemporal nerve. Surg
Radiol Anat 26:494–500. Zufferey JA 2013 Is the malaris muscle the antianging missing link of the
Langdon JD 1998 Parotid surgery. In: Langdon JD, Patel MF (eds) Operative midface? Eur J Plast Surg 36:345–52.
Maxillofacial Surgery. London: Chapman & Hall; pp. 381–90.
A detailed account of the procedures for the safe dissection of the
intraparotid part of the facial nerve.
FURTHER READING
Norman JE de, McGurk M (eds) 1995 Color Atlas and Text of the Salivary
Glands. London: Mosby–Wolfe.


Face and scalp
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A
Procerus
Superior oblique
Corrugator supercilii Orbicularis oculi
Medial rectus Upper orbital part
Palpebral parts
Levator palpebrae
Lacrimal part
superioris
Lower orbital part
Superior rectus
Temporalis
Levator labii superioris
Lateral rectus alaeque nasi
Nasalis, transverse part
Levator labii superioris
Levator anguli oris
Zygomaticus major
Inferior rectus
Zygomaticus minor
Inferior oblique Masseter
Nasalis, alar part
Sternocleidomastoid Stylopharyngeus
Masseter
Styloglossus
Temporalis
Buccinator
Incisivus labii superioris
Depressor septi
Depressor anguli oris
Platysma
Depressor labii inferioris
Incisivus labii inferioris
Mentalis
Fig. 30.17 A, An anterior view of the skull, showing the muscle attachments. Continued
EPICRANIAL MUSCLE GROUP horror). Acting from below, the frontal parts draw the scalp forwards,
throwing the forehead into transverse wrinkles. The occipital parts draw
Epicranius the scalp backwards. Acting alternately, the occipital and frontal parts
can move the entire scalp backwards and forwards.
Epicranius consists of occipitofrontalis and temporoparietalis.
Occipitofrontalis Variations A thin muscular slip, transversus nuchae, is sometimes
present. It arises from the external occipital protuberance or from the
Occipitofrontalis covers the dome of the skull from the highest nuchal
superior nuchal line, either superficial or deep to trapezius. It is fre
lines to the eyebrows. It is a broad, musculofibrous layer and consists
quently inserted with auricularis posterior but may blend with the
of four thin, muscular quadrilateral parts, two occipital and two frontal,
posterior edge of sternocleidomastoid.
connected by the epicranial aponeurosis. Each occipital part (occipi
talis) arises by tendinous fibres from the lateral twothirds of the highest
epicranial aponeurosis


nuchal line of the occipital bone and the adjacent region of the mastoid
part of the temporal bone, and extends forwards to join the aponeurosis. The epicranial aponeurosis covers the upper part of the cranium and,
The gap between the two occipital parts is occupied by an extension of with the epicranial muscle, forms a continuous fibromuscular sheet that
the epicranial aponeurosis. Each frontal part (frontalis) is adherent to extends from the occiput to the eyebrows. Posteriorly, between the
the superficial fascia, particularly of the eyebrows. Although frontalis has occipital parts of occipitofrontalis, it is attached to the external protu
no bony attachments of its own, its fibres blend with those of adjacent berance and highest nuchal line of the occipital bone. Anteriorly, it
muscles – procerus, corrugator supercilii and orbicularis oculi – and splits to enclose the frontal parts and sends a short, narrow prolong
ascend to join the epicranial aponeurosis in front of the coronal suture. ation between them. Laterally, the anterior and superior auricular
muscles are attached to it; the aponeurosis is thinner, and continues
Vascular supply Occipitofrontalis is supplied by branches of the over the temporal fascia to the zygomatic arch. It is united to the skin
superficial temporal, ophthalmic, posterior auricular and occipital lying over the cranial vault by fibrous superficial fascia, but it is con
arteries. nected more loosely to the underlying pericranium by areolar tissue, an
arrangement that allows it to move freely, carrying with it the skin of
Innervation The occipital part of occipitofrontalis is supplied by the the scalp.
posterior auricular branch of the facial nerve, and the frontal part is
supplied by the temporal branches of the facial nerve. Temporoparietalis
Temporoparietalis is a variably developed sheet of muscle that lies
Actions Acting from above, the frontal parts raise the eyebrows and between the frontal parts of occipitofrontalis and the anterior and
the skin over the root of the nose (e.g. as in expressions of surprise or superior auricular muscles.


Muscles of the face
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B
Musculus uvulae
Medial pterygoid
Tensor veli palatini
(palatine aponeurosis) Lateral pterygoid
Longus capitis
Tensor veli palatini
Rectus capitis anterior
Superior pharyngeal constrictor
Styloglossus
Masseter
Stylohyoid
Temporalis
Rectus capitis lateralis
Tensor tympani
Rectus capitis posterior minor
Stylopharyngeus
Digastric, posterior belly
Longissimus capitis
Splenius capitis
Levator veli palatini
Obliquus capitis superior
Sternocleidomastoid
Rectus capitis posterior major
Occipitalis
Semispinalis capitis Trapezius
C
Temporalis
Auricularis posterior
Zygomaticus major
Occipitalis
Zygomaticus minor
Inferior oblique
Sternocleidomastoid
Corrugator supercilii
Orbicularis oculi
Splenius capitis
Levator labii superioris
alaeque nasi
Procerus Trapezius
Levator labii superioris Semispinalis capitis
Rectus capitis
Levator anguli oris posterior minor
Nasalis transversus
Rectus capitis
posterior major
Nasalis alaris Obliquus capitis superior
Longissimus capitis
Depressor septi
Rectus capitis anterior
Incisivus labii
superioris Stylopharyngeus
Stylohyoid
Mentalis
Styloglossus
Incisivus labii inferioris
Lateral pterygoid
Depressor labii inferioris
Masseter
Depressor anguli oris
Platysma Buccinator
Fig. 30.17, cont’d B, A basal view of the skull, showing the muscle attachments. C, A lateral view of the skull, showing muscle attachments.


Face and scalp
492
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nOITces
A
Epicranial aponeurosis Procerus
Occipitofrontalis, frontal belly Corrugator supercilii
Depressor supercilii Levator labii superioris alaeque nasi
Nasalis
Orbicularis oculi, palpebral part
Orbicularis oculi, orbital part
Levator labii superioris alaeque nasi
Levator labii superioris
Orbicularis oculi, orbital part
Zygomaticus minor
Levator labii superioris
Zygomaticus major
Zygomaticus minor
Zygomaticus major
Parotid gland
Orbicularis oris, marginal part
Levator anguli oris
Levator anguli oris
Buccal fat pad
Risorius
Parotid duct
Depressor labii inferioris
Buccinator
Depressor anguli oris
Masseter, superficial part
Platysma
Depressor anguli oris
Depressor labii inferioris
Mentalis Platysma
Depressor septi nasi Orbicularis oris, labial part
B
Auricularis anterior Epicranial aponeurosis
Occipitofrontalis, frontal belly
Orbicularis oculi, palpebral part Auricularis superior
Depressor supercilii
Occipitofrontalis,
Procerus occipital belly
Orbicularis oculi, orbital part
Auricularis posterior
Levator labii superioris alaeque nasi
Nasalis
Sternocleidomastoid
Levator labii superioris
Zygomaticus minor Semispinalis capitis
Orbicularis oris
Splenius capitis
Zygomaticus major
Orbicularis oris
Trapezius
Depressor labii inferioris
Cervical fascia, investing layer
Mentalis (superficial layer)
Depressor anguli oris
Parotid fascia
Risorius Platysma
Fig. 30.18 The superficial muscles of the head and neck. A, Frontal view. B–D, The muscles of the left lateral side of the head and upper part of the


neck, shown at progressively deeper levels. (With permission from Waschke J, Paulsen F (eds), Sobotta Atlas of Human Anatomy, 15th ed, Elsevier,
Urban & Fischer. Copyright 2013.)


Muscles of the face
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ReTpaHc
C
Pericranium
Temporal fascia, deep layer
Corrugator supercilii Temporal fascia, superficial layer
Procerus
Accessory parotid gland
Parotid duct
Levator anguli oris Parotid gland
Sternocleidomastoid
Zygomaticus major
Depressor labii inferioris
Masseter
Mentalis
Risorius Buccal fat pad
Digastric, anterior belly Submandibular gland
Cervical fascia, investing layer
(superficial layer)
D
Temporalis
Corrugator supercilii
Temporomandibular joint, lateral ligament
Levator labii superioris alaeque nasi
Ramus of mandible
Levator labii superioris
Infraorbital nerve Cartilaginous external acoustic meatus
Levator anguli oris Superficial temporal artery;
styloglossus
Styloid process
Parotid duct
Buccinator
Digastric, posterior belly
Masseter, deep part
Sternocleidomastoid
Mentalis
Splenius capitis
Depressor labii inferioris
Levator scapulae
Depressor anguli oris
Vagus nerve
Digastric, anterior belly
Hyoid bone Scalenus medius
Masseter, superficial part
Scalenus posterior
Thyrohyoid
Internal jugular vein
Stylohyoid
Common carotid artery
Omohyoid
Inferior
Sternohyoid constrictor Brachial plexus
of pharynx
Hypoglossal nerve Scalenus anterior
Sternothyroid
Fig. 30.18, cont’d


Face and scalp
494
4
nOITces
CIRCUMORBITAL AND PALPEBRAL MUSCLE GROUP Actions Corrugator supercilii cooperates with orbicularis oculi to
draw the eyebrows medially and downwards to shield the eyes in bright
The circumorbital and palpebral group of muscles are orbicularis oculi, sunlight. It is also involved in frowning. The combined action of the
corrugator supercilii and levator palpebrae superioris. The first two are two muscles produces mainly vertical wrinkles on the supranasal strip
described here; levator palpebrae superioris is described on page 670. of the forehead.
Orbicularis oculi
Orbicularis oculi is a broad, flat, elliptical muscle that surrounds the NASAL MUSCLE GROUP
circumference of the orbit and spreads into the adjacent regions of the
eyelids, anterior temporal region, infraorbital cheek and superciliary The nasal muscle group, which consists of procerus, nasalis and depres
region (see Fig. 30.18). It has orbital, palpebral and lacrimal parts, and sor septi, is described on page 558.
a small ciliary bundle.
The orbital part arises from the nasal component of the frontal bone,
the frontal process of the maxilla and from the medial palpebral liga BUCCOLABIAL MUSCLE GROUP
ment. The fibres form complete ellipses, without interruption on the
lateral side, where there is no bony attachment. The upper orbital fibres The shape of the mouth and the posture of the lips are controlled by a
blend with the frontal part of occipitofrontalis and corrugator supercilii. complex threedimensional assembly of muscular slips (Yousif and
Many of them are inserted into the skin and subcutaneous tissue of the Mendelson 1995). These include elevators, retractors and evertors of
eyebrow and constitute depressor supercilii. Inferiorly and medially, the the upper lip (levator labii superioris alaeque nasi, levator labii superi
ellipses overlap or blend to some extent with adjacent muscles (levator oris, zygomaticus major and minor, levator anguli oris and risorius);


labii superioris alaeque nasi, levator labii superioris and zygomaticus depressors, retractors and evertors of the lower lip (depressor labii
minor). At the extreme periphery, sectors of complete, and sometimes inferioris, depressor anguli oris, and mentalis); a compound sphincter
incomplete, ellipses have a loose areolar connection with the temporal (orbicularis oris, incisivus superior and inferior); and buccinator (see
extension of the epicranial aponeurosis. Fig. 30.18).
The palpebral part arises from the medial palpebral ligament, mainly
Levator labii superioris alaeque nasi
from its superficial surface, and from the bone immediately above and
below the ligament. The fibres sweep across the eyelids anterior to the Levator labii superioris alaeque nasi is described on page 559.
orbital septum, interlacing at the lateral commissure to form the lateral
Levator labii superioris
palpebral raphe. A small group of fine fibres, close to the margin of each
eyelid behind the eyelashes, constitutes the ciliary bundle. Levator labii superioris arises from the maxilla and zygomatic bone
The lacrimal part arises from the upper part of the lacrimal crest, and above the infraorbital foramen. Its fibres converge into the muscular
the adjacent lateral surface, of the lacrimal bone. It passes laterally substance of the upper lip between the lateral slip of levator labii su
behind the nasolacrimal sac (where some fibres are inserted into the perioris alaeque nasi and zygomaticus minor.
associated fascia) and divides into upper and lower slips. Some fibres
are inserted into the tarsi of the eyelids close to the lacrimal canaliculi, Vascular supply Levator labii superioris is supplied by the facial
but most continue across in front of the tarsi and interlace in the lateral artery and the infraorbital branch of the maxillary artery.
palpebral raphe.
Innervation Levator labii superioris is innervated by the zygomatic
Vascular supply Orbicularis oculi is supplied by branches of the and buccal branches of the facial nerve.
facial, superficial temporal, maxillary and ophthalmic arteries.


Actions Levator labii superioris elevates and everts the upper lip.
Innervation Orbicularis oculi is supplied by temporal and zygomatic Acting with other muscles, it modifies the nasolabial furrow. In some
branches of the facial nerve. faces, this furrow is a highly characteristic feature and it is often deep
ened in expressions of sadness or seriousness.
Actions Orbicularis oculi is the sphincter muscle of the eyelids and
plays an important role in facial expression and various ocular reflexes. Zygomaticus major
The orbital portion is usually activated under voluntary control. Con
Zygomaticus major arises from the zygomatic bone, just in front of the
traction of the upper orbital fibres produces vertical furrowing above
zygomaticotemporal suture, and passes to the angle of the mouth where
the bridge of the nose, narrowing of the palpebral fissure, and bunching
it blends with the fibres of levator anguli oris, orbicularis oris and more
and protrusion of the eyebrows, which reduces the amount of light
deeply placed muscular bands.
entering the eyes. Eye closure is largely affected by lowering of the upper
eyelid but there is also considerable elevation of the lower eyelid. The Vascular supply Zygomaticus major is supplied by the superior
palpebral portion can be contracted voluntarily, to close the lids gently
labial branch of the facial artery.
as in sleep, or reflexly, to close the lids protectively in blinking. The
palpebral part has upper depressor and lower elevator fascicles. The Innervation Zygomaticus major is innervated by the zygomatic and
lacrimal part of the muscle draws the eyelids and the lacrimal papillae
buccal branches of the facial nerve.
medially, thereby exerting traction on the lacrimal fascia, and may aid
drainage of tears by dilating the lacrimal sac. It may also influence pres Actions Zygomaticus major draws the angle of the mouth upwards
sure gradients within the lacrimal gland and ducts. This activity may
and laterally, as in laughing.
assist in the sinuous flow of tears across the cornea, direct the lacrimal
punctum into the lacus lacrimalis, and express secretions of the ciliary Zygomaticus minor


and tarsal glands. When the entire orbicularis oculi muscle contracts,
Zygomaticus minor arises from the lateral surface of the zygomatic
the skin is thrown into folds that radiate from the lateral angle of the
bone immediately behind the zygomaticomaxillary suture, and passes
eyelids. Such folds, when permanent, cause wrinkles in middle age (the
downwards and medially into the muscular substance of the upper lip.
socalled ‘crow’s feet’).
Superiorly, it is separated from levator labii superioris by a narrow tri
Corrugator supercilii angular interval and, inferiorly, it blends with this muscle.
Corrugator supercilii is a small pyramidal muscle located at the medial
Vascular supply Zygomaticus minor is supplied by the superior
end of each eyebrow, lying deep to the frontal part of occipitofrontalis
labial branch of the facial artery.
and orbicularis oculi, with which it is partially blended (see Fig.
30.18A). It arises from bone at the medial end of the superciliary arch
Innervation Zygomaticus minor is innervated by the zygomatic and
and its fibres pass laterally and slightly upwards to exert traction on the
buccal branches of the facial nerve.
skin above the middle of the supraorbital margin.
Vascular supply Corrugator supercilii is supplied by branches from Actions Zygomaticus minor elevates the upper lip, exposing the max
adjacent arteries, mainly from the superficial temporal and ophthalmic illary teeth. It also assists in deepening and elevating the nasolabial
arteries. furrow. Acting together, the main elevators of the lip – levator labii
superioris alaeque nasi, levator labii superioris and zygomaticus minor
Innervation Corrugator supercilii is innervated by temporal branches – curl the upper lip in smiling and in expressing smugness, contempt
of the facial nerve. or disdain.


Muscles of the face
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Levator anguli oris Innervation Depressor anguli oris is innervated by the buccal and
Levator anguli oris arises from the canine fossa of the maxilla, just mandibular branches of the facial nerve.
below the infraorbital foramen, and inserts into and below the angle
of the mouth. Its fibres mingle there with other muscle fibres (zygo Actions Depressor anguli oris draws the angle of the mouth down
maticus major, depressor anguli oris, orbicularis oris). Some superficial wards and laterally in opening the mouth and in expressing sadness.
fibres curve anteriorly and attach to the dermal floor of the lower part During opening of the mouth, the mentolabial sulcus becomes more
of the nasolabial furrow. The infraorbital nerve and accompanying horizontal and its central part deepens.
vessels enter the face via the infraorbital foramen between the origins
Buccinator
of levator anguli oris and levator labii superioris.
The muscle of the cheek, buccinator, is a thin quadrilateral muscle that
Vascular supply Levator anguli oris is supplied by the superior labial occupies the interval between the maxilla and the mandible (see Fig.
branch of the facial artery and the infraorbital branch of the maxillary 30.18D). Its upper and lower boundaries are attached to the outer
artery. surfaces of the alveolar processes of the maxilla and mandible, respec
tively, opposite the molar teeth, and its posterior border is attached to
Innervation Levator anguli oris is innervated by the zygomatic and the anterior margin of the pterygomandibular raphe. In addition, a few
buccal branches of the facial nerve. fibres spring from a fine tendinous band that bridges the interval
between the maxilla and the pterygoid hamulus, between the tuberosity
Actions Levator anguli oris raises the angle of the mouth in smiling, of the maxilla and the upper end of the pterygomandibular raphe. On
and contributes to the depth and contour of the nasolabial furrow. its way to the soft palate, the tendon of tensor veli palatini pierces the


pharyngeal wall in the small gap that lies behind this tendinous band.
Malaris
The posterior part of buccinator is deeply placed, internal to the man
Malaris is a thin sheet of muscle that is sometimes found covering and dibular ramus and in the plane of the medial pterygoid plate. Its anterior
blending with zygomaticus major and minor, and levator labii superi component curves out behind the third molar tooth to lie in the sub
oris. It is subject to considerable variation (Zufferey 2013). When mucosa of the cheek and lips. The fibres of buccinator converge towards
present, it is continuous with the inferior limit of orbicularis oculi, from the modiolus near the angle of the mouth. Here the central (pterygo
which it is possibly derived. Its fibres incline medially and downwards. mandibular) fibres intersect, those from below cross to the upper part
Some of its superficial fascicles have a dermal attachment to the naso of orbicularis oris, and those from above cross to the lower part. The
labial ridge and sulcus, and others pass directly to the angle of the highest (maxillary) and lowest (mandibular) fibres of buccinator con
mouth and to the outer third of the upper lip to intersect with bundles tinue forwards to enter their corresponding lips without decussation.
of orbicularis oris. As buccinator courses through the cheek and modiolus, substantial
numbers of its fibres are diverted internally to attach to submucosa.
Mentalis
Mentalis is a conical fasciculus lying at the side of the frenulum of the Relations Posteriorly, buccinator lies in the same plane as the su
lower lip. The fibres arise from the incisive fossa of the mandible and
perior pharyngeal constrictor, which arises from the posterior margin
descend to attach to the skin of the chin.
of the pterygomandibular raphe, and is covered there by the buccopha
ryngeal fascia. Superficially, the buccal pad of fat separates the posterior
Vascular supply Mentalis is supplied by the inferior labial branch
part of buccinator from the ramus of the mandible, masseter and part


of the facial artery and the mental branch of the maxillary artery.
of temporalis. Anteriorly, the superficial surface of buccinator is related
to zygomaticus major, risorius, levator and depressor anguli oris, and
Innervation Mentalis is innervated by the mandibular branch of the
the parotid duct. It is crossed by the facial artery, facial vein and branches
facial nerve.
of the facial and buccal nerves. The deep surface of buccinator is related
Actions Mentalis raises the lower lip, wrinkling the skin of the chin. to the buccal glands and mucous membrane of the mouth. The parotid
duct pierces buccinator opposite the third upper molar tooth, and lies
It raises the base of the lower lip and therefore helps in protruding and
on the deep surface of the muscle before opening into the mouth
everting the lower lip in drinking and also in expressing doubt or
opposite the maxillary second molar tooth.
disdain.
Depressor labii inferioris Vascular supply Buccinator is supplied by branches from the facial
Depressor labii inferioris is a quadrilateral muscle that arises from the artery and the buccal branch of the maxillary artery.
oblique line of the mandible, between the symphysis menti and the
mental foramen. It passes upwards and medially into the skin and Innervation Buccinator is supplied by the buccal branch of the facial
mucosa of the lower lip, blending with its contralateral fellow and with nerve.
orbicularis oris. Below and laterally, it is continuous with platysma.
Actions Buccinator compresses the cheek against the teeth and gums
Vascular supply Depressor labii inferioris is supplied by the inferior during mastication, and assists the tongue in directing food between
labial branch of the facial artery and the mental branch of the maxillary the teeth. As the mouth closes, the teeth glide over the buccolabial
artery. mucosa, which must be retracted progressively from their occlusal sur
faces by buccinator and other submucosally attached muscles. When
Innervation Depressor labii inferioris is innervated by the mandibular the cheeks have been distended with air, the buccinators expel it


branch of the facial nerve. between the lips, an activity important when playing wind instruments,
and which accounts for the name of the muscle (Latin buccinator =
Actions Depressor labii inferioris draws the lower lip downwards and trumpeter).
a little laterally in masticatory activity, and may assist in eversion of the
Pterygomandibular raphe
lower lip. It contributes to the expressions of irony, sorrow, melancholy
and doubt. The pterygomandibular raphe is a thin band of tendinous fibres that
stretches from the hamulus of the medial pterygoid plate down to the
Depressor anguli oris
posterior end of the mylohyoid line of the mandible. It is easily pal
Depressor anguli oris has a long, linear origin from the mental tubercle pated medially, where it is covered by the mucous membrane of the
of the mandible and its continuation, the oblique line, below and mouth, and laterally it is separated from the ramus of the mandible by
lateral to depressor labii inferioris. It converges into a narrow fasciculus a quantity of adipose tissue. It gives attachment posteriorly to the su
that blends at the angle of the mouth with orbicularis oris and risorius, perior constrictor of the pharynx, and anteriorly to the central part of
and some fibres continue into levator anguli oris. Depressor anguli oris buccinator. The pterygomandibular raphe (see Fig. 31.1) is a useful ana
is continuous below with platysma and cervical fasciae. Some of its tomical landmark for the administration of inferior alveolar nerve
fibres may pass below the mental tubercle and cross the midline to blocks because the nerve lies lateral to it.
interlace with their contralateral fellows, thereby forming transversus
Orbicularis oris
menti (the ‘mental sling’).
Orbicularis oris is so named because it was once assumed that the oral
Vascular supply Depressor anguli oris is supplied by the inferior fissure was surrounded by a series of complete ellipses of striated muscle


labial branch of the facial artery and the mental branch of the maxillary that acted together in the manner of a sphincter. However, it is now
artery. recognized that the muscle actually consists of four substantially


Face and scalp
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4
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independent quadrants (upper, lower, left and right), each of which Actions The actions of orbicularis oris are considered in detail in the
contains a larger pars peripheralis and a smaller pars marginalis. Mar next section.
ginal and peripheral parts are apposed along lines that correspond
externally to the lines of junction between the vermilion zone of the Incisivus labii superioris
lip and the skin. Thus, orbicularis oris is composed of eight segments, Incisivus labii superioris has a bony origin from the floor of the incisive
each of which is named systematically according to its location. Each fossa of the maxilla above the eminence of the lateral incisor tooth.
segment resembles a fan that has its stem at the modiolus and is open Initially, it lies deep to the superior part of orbicularis oris pars periph
in peripheral segments and almost closed in marginal segments. eralis. Arching laterally, its fibre bundles become intercalated between,
and parallel to, the orbicular bundles. Approaching the modiolus, it
pars peripheralis
segregates into superficial and deep parts; the former blends partially
Pars peripheralis has, in each quadrant, a lateral stem attached to the
with levator anguli oris and attaches to the body and apex of the modio
labial side of the modiolus over its full thickness, from apex to base,
lus, and the latter is attached to the superior cornu and base of the
including the corresponding upper or lower cornu. Most of these stem
modiolus.
fibres are thought to originate within the modiolus (although it is pos
sible that some are direct continuations from the other modiolar Incisivus labii inferioris
muscles). The consensus view is that stem fibres are reinforced directly Incisivus labii inferioris, an accessory muscle of the orbicularis oris
by fibres from buccinator (upper fibres and decussating lower central muscle complex, has many features in common with incisivus labii
fibres), levator anguli oris and the superficial part of zygomaticus major superioris. Its osseous attachment is to the floor of the incisive fossa of


in the upper lip, and from buccinator (lower fibres and decussating the mandible, lateral to mentalis and below the eminence of the lateral
upper central fibres) and depressor anguli oris in the lower lip. incisor tooth. Curving laterally and upwards, it blends to some extent
The fibres of orbicularis oris enter their respective superior and in with the inferior part of orbicularis oris pars peripheralis before reach
ferior labial areas, and diverge to form triangular muscular sheets. These ing the modiolus, where superficial bundles attach to the apex and
are thickest at the junctions between skin and the vermilion zone, and body, and deep bundles attach to the base and inferior cornu.
become progressively thinner as they reach the limits of the labial
region (as defined above). The greater part of each sheet enters the free Platysma
lip, where its fibres aggregate into cylindrical bundles orientated parallel Platysma is described as a muscle of the neck but it is considered
to the vermilion zone. Fibres of the direct labial tractors pass to their here as a contributor to the orbicularis oris muscle complex. It has
submucosal attachments between these cylindrical bundles and between mandibular, labial and modiolar parts. Pars mandibularis attaches to
pars peripheralis and pars marginalis. In the upper lip, the highest fibres the lower border of the body of the mandible. Posterior to this attach
run near the nasolabial sulcus, a few fibres attach to the sulcus, and a ment, a substantial flattened bundle separates and passes superomedi
few to the nasal ala and septum. In the lower lip, the lowest fibres reach ally to the lateral border of depressor anguli oris, where a few fibres
and attach to the mentolabial sulcus. A small proportion of the main join this muscle. The remainder continue deep to depressor anguli oris
body of fibres is thought to end in the labial connective tissue, dermis and reappear at its medial border. Here, they continue within the tissue
or submucosa as it traverses its quadrant of free lip. Most fibres continue of the lateral half of the lower lip, as a direct labial tractor, platysma


towards the median plane and cross some 5 mm into the opposite pars labialis. Pars labialis occupies the interval between depressor
halflip. At this point, the fibres from the two sides interlace on their anguli oris and depressor labii inferioris, and is in the same plane
way to their dermal insertions, creating the ridges of the philtrum of as these muscles. The adjacent margins of all three muscles blend and
the upper lip and the less marked corresponding depression in the they have similar labial attachments. Platysma pars modiolaris consti
lower lip. tutes all the remaining bundles posterior to pars labialis, other than
a few fine fascicles that end directly in buccal dermis or submucosa.
pars marginalis
Pars modiolaris is posterolateral to depressor anguli oris and passes
Pars marginalis of orbicularis oris is developed to a unique extent in
superomedially, deep to risorius, to apical and subapical modiolar
human lips and is closely associated with speech and the production
attachments.
of some kinds of musical tone. In each quadrant, the pars marginalis
consists of a single (occasionally double) band of narrowdiameter Risorius
muscle fibres lodged within the tissues of each vermilion zone. At their
Risorius is a highly variable muscle that ranges from one or more
medial end, the marginal fibres meet and interlace with their contra
slender fascicles to a wide, thin, superficial fan. Its peripheral attach
lateral fellows and then attach to the dermis of the vermilion zone a
ments may include some or all of the following: the zygomatic arch,
few millimetres beyond the median plane in a manner similar to pars
parotid fascia, fascia over the masseter anterior to the parotid, fascia
peripheralis. At their lateral ends, the fibres converge and attach to the
enclosing platysma pars modiolaris, and fascia over the mastoid pro
deepest part of the modiolar base along a horizontal strip level with
cess. Its fibres converge to apical and subapical attachments at the
the buccal angle.
modiolus.
The relations between pars marginalis and pars peripheralis are


complex. In a fullthickness section of an upper lip at right angles to Vascular supply Risorius is supplied mainly by the superior labial
the vermilion zone, the cylindrical bundles of peripheralis fibres form
branch of the facial artery.
an S shape, with an external convexity above and an internal convexity
below; the classic analogy is to the shank and initial curved part of a Nerve supply Risorius is supplied by buccal branches of the facial
hook. Beyond peripheralis, the hook shape is completed by the blunted
nerve.
triangular profile of marginalis, which occupies the core of the vermil
ion zone with its base adjacent to peripheralis and its apex reaching Actions Risorius pulls the corner of the mouth laterally in numerous
upwards and anteriorly towards the junction between vermilion zone
facial activities, including grinning and laughing.
and skin. In a similar section through the lower lip, peripheralis bundles
form a continuous curve that is concave towards the external surface.
This is surmounted by the flattened triangular profile of marginalis, MOVEMENTS OF THE FACE AND LIPS
which curves anteriorly, its apex again nearing the vermilion/cutaneous
junction. Thus, throughout the vermilion zones of both lips, marginalis Direct labial tractors
lies substantially anterior to the adjacent bundles of peripheralis.
Direct labial tractors, as their name suggests, pass directly into the
However, as the muscles are traced laterally beyond the vermilion zone
tissues of the lips and not via the modioli. In broad terms, the force
and across the buccal angle, this relationship alters and marginalis
exerted by tractors is directed vertically at an approximate right angle
becomes inverted as it wraps progressively around the adjacent edge of
to the oral fissure. Their action will therefore elevate and/or evert the
peripheralis to reach its deep (submucosal) surface, and maintains this
whole, or part, of the upper lip and depress and/or evert the whole, or
position up to its attachment at the modiolar base.
part, of the lower lip. The tractors are, from medial to lateral, the labial
Vascular supply Orbicularis oris is supplied mainly by the superior part of levator labii superioris alaeque nasi; levator labii superioris and


and inferior labial branches of the facial artery, the mental and infra zygomaticus minor in the upper lip; and depressor labii inferioris and
orbital branches of the maxillary artery, and the transverse facial branch platysma pars labialis in the lower lip.
of the superficial temporal artery. In both upper and lower lips, the tractors blend into a continuous
sheet that divides into a series of superimposed coronal sheets that are
Nerve supply Orbicularis oris is supplied by the buccal and man anterior to the muscle bundles of orbicularis oris pars peripheralis as
dibular branches of the facial nerve. they enter the free lip. The sheets may be divided into three groups at


Muscles of the face
497
03
ReTpaHc
A B The modiolus and its role
Direct in facial movements
labial tractors
On each side of the face, a number of muscles converge towards a focus
just lateral to the buccal angle, where they interlace to form a dense,
Orbicularis
compact, mobile, fibromuscular mass called the modiolus. This can be
oris, pars
peripheralis palpated most effectively by using the opposed thumb and index finger
to compress the mucosa and skin simultaneously. At least nine muscles,
Mucosal
attachment depending on the classification employed, are attached to each modi
olus. Moreover, the muscles lie in different planes, their modiolar stems
Dermal
are often spiralized, and most divide into two bundles – some into three
attachment
or four, each of them interlacing and attaching in a distinctive way. Not
surprisingly, therefore, the threedimensional organization of the modi
olus has proved difficult to analyse.
The shape and dimensions of the modiolus are given approximately
Orbicularis oris,
because they are subject to individual, age, sexual and ethnic variation.
pars marginalis
Furthermore, the modiolus has no precise histological boundaries, and
is an irregular zone where dense, compact, interlacing tissue grades into
Vermilion zone
the stems of individually recognizable muscles. The modiolus has the
rough form of a blunt cone. The base of the cone (basis moduli) is
adjacent and adherent to the mucosa. It is roughly elliptical in outline
Fig. 30.19 A, A sagittal section of the upper lip in repose. On the left is and extends vertically 20 mm above and 20 mm below a horizontal
thin skin with oblique hair follicles; on the right is thick mucosa with line through the buccal angle. It also extends laterally a similar distance
mucous glands and mucosal shelf; between them is the vermilion from the angle. The blunt apex of the cone (apex moduli) is 4 mm
zone. B, As A but slightly contracted, forming a narrowed profile (labial
across, and is centred approximately 12 mm lateral to the buccal angle.
cord).
From mucosa to dermis, the thickness of the mass is usually 10 mm,


divided approximately equally into basal, central and apical parts. The
central body has an oblique fibrous cleft or channel that transmits the
increasing depths from the skin surface, each with a distinct zone of facial artery, an arrangement that may limit the extent to which it is
attachment (Fig. 30.19). The superficial group comprises a succession compressed by contraction of the buccolabial musculature. The cone
of fine fibre bundles, which curve anteriorly a short distance before shape is modified by two roundedged flanges (or cornua) that extend
attaching in a series of horizontal rows to the dermis between the hair into the lateral free lip tissues above and below the corner of the mouth.
follicles, sebaceous glands and sweat glands. The intermediate group The tip of the superior cornu extends 5.5 mm medial to the buccal
attaches to the dermis of the vermilion zone, which they reach by two angle, the tip of the inferior cornu only 3.5 mm. With these additions,
routes: the more superficial bundles continue past the skin/vermilion the modiolar base becomes kidneyshaped, with the buccal angle pro
junction, then curve posteriorly over orbicularis oris pars marginalis to jecting towards the hilum.
punctate attachments on the ventral half of the dermis of the vermilion The apex of the modiolus is deep and adherent to the panniculus
zone, while the deeper bundles first pass posteriorly between pars carnosus, which extends posteromedially as a thin, sloping sheet down
peripheralis and pars marginalis, then curve anteriorly to punctate to the buccal angle. There, its free border forms a crescentic, narrow,
attachments on the dorsal half of the dermis of the vermilion zone. The flexible, subcutaneous, fibroelastic cord that accommodates the varying
deep group is closely applied to the anterior surface of orbicularis oris postures of the modioli, lips, mouth and jaws.
pars peripheralis, and sends fine tractor fibres between its parallel Controlled threedimensional mobility of the modioli enables them
bundles to attach posteriorly into the submucosa and periglandular to integrate the activities of the cheeks, lips and oral fissure, the oral


connective tissue. vestibule and the jaws. Such activities include biting, chewing, drinking,
sucking, swallowing, changes in vestibular contents and pressure, the
Movements of the lips
innumerable subtle variations involved in speech, the modulation (and
The various groups of direct labial tractors may act together or individu occasional generation) of musical tones, production of harsher sounds
ally, and their effects may involve a complete labial quadrant or be in shouting and screaming, crying, and all the permutations of facial
restricted to a short segment. For example, partial contraction of the expression, ranging from mere hints to gross distortion, symmetric or
superior labial tractors can result in localized elevation of a segment of asymmetric. Major modiolar movements appear to involve many, if not
the upper lip, in a postural expression reminiscent of the ‘canine snarl’. all, of its associated muscles, and there is little value in considering the
Normally, however, the activity of the tractors is modified by the super actions of the individual muscles in isolation. While the most obvious
imposed activity of orbicularis oris and the modiolar muscles. The determinant of modiolar position and mobility is the balance between
resultant actions range from delicate adjustments of the tension and the forces exerted by muscles that are directly attached to it, another
profile of the lip margins to large increases of the oral fissure with ever influential factor is the degree of separation or ‘gape’ between the upper
sion of the lips. and lower teeth. Starting from the occlusal position, and with the lips
Lip protrusion is passive in its initial stages. It may be suppressed by maintained in contact, the teeth can be separated by approximately
powerful contraction of the whole of orbicularis oris or enhanced by 1.25 cm near the midline, and the mentolabial sulcus descends by a
selective activation of parts of the direct labial tractors. However, lip similar distance. With further separation, the lips part, and as gape
movements must accommodate separation of the teeth brought about increases to its maximum, interlabial and interdental distances approach
by mandibular depression at the temporomandibular joints. Beyond a 4 cm, at which point the mentolabial sulcus has descended a further


certain range of mouth opening, labial movements are almost com 2 cm. In this posture, the modiolus has descended about 1 cm to lie
pletely dominated by mandibular movements. Thus, over the last over the interdental space, into which its basal and surrounding buccal
2.5–3 cm interincisal distance of wide jaw separation, strong contrac mucosa projects a few millimetres, and its cornua diverge into their
tion of orbicularis oris cannot effect lip contact, and instead it causes respective lips at an obtuse angle to each other, the dispositions of the
fullthickness inflection of upper and lower lips, including the vermil modiolar muscles being correspondingly modified. The general hexag
ion zone, towards the oral cavity, wrapping them around the incisal onal shape of the labial area changes as the mouth and jaws open
edges, canine cusps and premolar occlusal surfaces. The involvement of progressively. In maximal opening, the distance between the superior
the lips in speech is described in Chapter 35, but some aspects relevant and inferior boundaries has increased by 3–3.5 cm at the centre; the
to the actions of orbicularis oris pars marginalis will be described here. transverse distance between its lateral angles has decreased by 1 cm
Contraction of marginalis is considered to alter the crosssectional and the angles are obtuse; the nasolabial sulci are longer, straighter and
profile of the free margin of the vermilion zone such that both the more vertical; and the inferior buccolabial sulci are less deep and
gentle bulbous profile of the upper lip and the smooth posterosuperior curved. These soft tissue changes radiate from the bilateral modioli.
convexity of the lower lip change to a narrow, symmetric, triangular With the lips in contact and the teeth in tight occlusion, the modi
profile. The transformed rims, whose length and tension can be deli olus can move a few millimetres in all directions. However, mobility is
cately controlled, have been named labial cords. They are known to be maximal when there is 2–3 mm clearance between the teeth; the apex
involved in the production of some consonantal (labial) sounds. A of the modiolus may then move vertically upwards 10 mm, downwards


labial cord may also function as a ‘vibrating reed’ in whistling or playing 5 mm, posterolaterally 10 mm, and anteromedially 10 mm, these
a wind instrument such as the trumpet. movements occurring in the curved planes of the cheek and lips.


Face and scalp
498
4
nOITces
Fig. 30.20 The arteries and
veins of the left side of the
face, head and neck and
their main branches. The
infraorbital artery is shown
in Figure 26.1.
Zygomaticotemporal
artery and vein Zygomaticofacial
artery and vein
Supratrochlear
artery and vein Transverse facial
artery and vein
Supraorbital
artery and vein
Superficial temporal
artery and vein
Angular artery
and vein
Occipital artery and vein
Lateral nasal
artery and vein Posterior auricular vein
Superior labial
Posterior auricular artery
artery and vein
Occipital vein
Occipital artery
Inferior labial External jugular vein
artery and vein
Facial artery Internal jugular vein
Facial vein
External carotid artery
Specific movements of the modiolus may occur to any point, and along Facial artery
any path, within the boundaries of the envelope of movement thus
defined. When the mouth is opened wide, the modiolus becomes
The facial artery arises in the neck from the external carotid artery
immobile. From the neutral position, the modiolus may be displaced
(see Figs 26.1, 29.8). It initially lies beneath platysma, passing on to
superficially along its apicobasal axis for up to 5–10 mm by liquids or
the face at the anteroinferior border of masseter, where its pulse can be
solids in the vestibule, or by an increase in air pressure that ‘balloons’
felt as it crosses the mandible. The artery is deep to skin, the fat of the
the cheeks and lips.
cheek and, near the angle of the mouth, zygomaticus major and riso
Many activities take place in three phases. Initially, a particular modi
rius, and superficial to buccinator and levator anguli oris. It may pass
olar muscle group becomes dominant over its antagonists and the
over or through levator labii superioris, and pursues a tortuous course
modiolus is rapidly relocated. Next, the modiolus is transiently fixed in
along the side of the nose towards the medial corner of the eye. At its


this new site by simultaneous contraction of modiolar muscles, princi
termination, it is embedded in levator labii superioris alaeque nasi.
pally zygomaticus major, levator anguli oris, depressor anguli oris and
Occasionally, the facial artery barely extends beyond the angle of the
platysma pars modiolaris, and this provides a fixed base from which
mouth, in which case its normal territory beyond this region is taken
the main physiological effectors, buccinator and orbicularis oris, carry
over by an enlarged transverse facial branch from the superficial tem
out their specific actions. These actions are usually integrated with
poral artery and by branches from the contralateral facial artery. The
partial separation or closure of the jaws, and with varying degrees of
facial vein is posterior to the artery and runs a more direct course across
activity in the direct labial tractors. All these factors combine to deter
the face. At the anterior border of masseter, the two vessels are in
mine the positions of the lips and oral fissure from moment to moment.
contact, whereas in the neck the vein is superficial to the artery.
Modiolar movements may be bilaterally symmetrical, unilateral or
The facial artery supplies branches to the muscles and skin of the
asymmetrical.
face (Fig. 30.20). Its named branches on the face are the premasseteric
artery, the superior and inferior labial arteries and the lateral nasal
artery. The part of the artery distal to its terminal branch is called the
MUSCLES OF MASTICATION
angular artery.
Masseter and temporalis, two of the muscles of mastication, are seen
Premasseteric artery The premasseteric artery is small and incon
on the face. Masseter covers the ramus of the mandible, and temporalis
stant. When present, it passes upwards along the anterior border of
lies over the temporal fossa. These muscles are described in detail with
masseter and supplies the surrounding tissues.
the other main muscles of mastication in Chapter 32.
Inferior labial artery The inferior labial artery arises near the angle
VASCULAR SUPPLY AND LYMPHATIC DRAINAGE of the mouth, passes upwards and forwards under depressor anguli oris,
and then penetrates orbicularis oris to run sinuously near the margin


OF THE FACE AND SCALP
of the lower lip, between the muscle and the mucous membrane. It
supplies the inferior labial glands, mucous membrane and muscles, and
ARTERIES anastomoses with its contralateral fellow and with the mental branch
of the inferior alveolar artery.
The main arterial supply to the face is derived from the facial and
superficial temporal arteries, with additional supply from branches of Superior labial artery The superior labial artery is larger and more
the maxillary and ophthalmic arteries. The back of the scalp is supplied tortuous than the inferior labial artery. It pursues a similar course along
by the posterior auricular and occipital arteries. There are numerous the superior labial margin, between the mucous membrane and orbicu
anastomoses between the branches. laris oris, anastomoses with its contralateral fellow, and supplies the


Vascular supply and lymphatic drainage of the face and scalp
499
03
ReTpaHc
upper lip. It gives off an alar branch and a septal branch, which ramifies Buccal artery The buccal artery is a branch of the second part of the
anteroinferiorly in the nasal septum. maxillary artery. It emerges on to the face from the infratemporal fossa,
crosses buccinator to supply the cheek, and anastomoses with the
Lateral nasal artery The lateral nasal artery is given off by the side infraorbital artery and with branches of the facial artery.
of the nose, supplies the dorsum and alae of nose, and anastomoses
with its contralateral fellow. The lateral nasal artery may be replaced by Infraorbital artery The infraorbital artery arises from the third part
a branch from the superior labial artery. of the maxillary artery. It runs through the infraorbital foramen and on
to the face, supplying the lower eyelid, the lateral aspect of the nose
Superficial temporal artery
and the upper lip. The infraorbital artery has extensive anastomoses
with the transverse facial and buccal arteries and with branches of the
The superficial temporal artery is the smaller terminal branch of the ophthalmic and facial arteries.
external carotid artery (see Figs 26.1, 30.20). It arises in the parotid
gland behind the neck of the mandible, where it is crossed by temporal Facial branches of the ophthalmic artery
and zygomatic branches of the facial nerve. Initially deep, it becomes
superficial as it passes over the posterior root of the zygomatic process
The ophthalmic artery is a branch of the internal carotid artery (see Fig.
of the temporal bone, where its pulse can be felt. It then runs up
41.3). Its supratrochlear, supraorbital, lacrimal, medial palpebral and
the scalp for approximately 4 cm and divides into frontal (anterior)
external (dorsal) nasal branches supply the face (see Fig. 30.20).
and parietal (posterior) branches. The artery is accompanied by corre
sponding veins, and by the auriculotemporal nerve, which lies just Supratrochlear artery The supratrochlear artery emerges from the


posterior to it.
orbit on to the face at the frontal notch. It supplies the medial parts of
The superficial temporal artery supplies the skin and muscles at the
the upper eyelid, forehead and scalp, and anastomoses with the supra
side of the face and in the scalp, the parotid gland and the temporo
orbital artery and with its contralateral fellow.
mandibular joint. It is occasionally biopsied when a histological diag
nosis of giant cell arteritis is required. The named branches of the Supraorbital artery The supraorbital artery leaves the orbit through
superficial temporal artery are the transverse facial, auricular, zygomatico
the supraorbital notch or foramen. It divides into superficial and deep
orbital, middle temporal, frontal and parietal arteries. The relative sizes branches that supply the skin and muscle of the upper eyelid, forehead
of the frontal, parietal and transverse facial branches vary; the frontal
and scalp. It anastomoses with the supratrochlear artery, frontal branch
and parietal branches may be absent, and the transverse facial may
of the superficial temporal and its contralateral fellow. At the supra
replace a shortened transverse facial artery.
orbital margin, it often sends a branch to the diploë of the frontal bone
and may also supply the mucoperiosteum in the frontal sinus.
Transverse facial artery The transverse facial artery arises before
the superficial temporal artery emerges from the parotid gland. It
Lacrimal artery The lacrimal artery appears on the face at the upper
traverses the gland, crosses masseter between the parotid duct and the
lateral corner of the orbit and supplies the lateral part of the eyelids.
zygomatic arch (accompanied by one or two facial nerve branches), and
Within the orbit, it gives off a zygomatic artery, which subdivides into
divides into numerous branches that supply the parotid gland and duct,
zygomaticofacial and zygomaticotemporal arteries. The zygomatico
masseter and adjacent skin. The branches anastomose with the facial,
facial artery passes through the lateral wall of the orbit to emerge on to
masseteric, buccal, lacrimal and infraorbital arteries, and may have a


the face at the zygomaticofacial foramen, and supplies the region over
direct origin from the external carotid artery.
lying the prominence of the cheek. The zygomaticotemporal artery also
Auricular artery The branches of the auricular artery are distributed passes through the lateral wall of the orbit, via the zygomaticotemporal
to the lobule and lateral surface of the auricle and to the external acous foramen, and supplies the skin over the nonbeard part of the temple.
tic meatus. The lacrimal artery anastomoses with the deep temporal branch of the
maxillary artery and the transverse facial branch of the superficial tem
Zygomatico-orbital artery The zygomaticoorbital artery may poral artery.
arise independently from the superficial temporal artery or from its
middle temporal or parietal branches. It runs close to the upper border Medial palpebral arteries Superior and inferior medial palpebral
of the zygomatic arch, between the two layers of temporal fascia, to the arteries arise from the ophthalmic artery below the trochlea. They
lateral orbital angle. It supplies orbicularis oculi and anastomoses with descend behind the nasolacrimal sac to enter the eyelids, where each
the lacrimal and palpebral branches of the ophthalmic artery. A well divides into two branches that course laterally along the edges of the
developed zygomaticoorbital artery is associated with a delayed div tarsal plates, forming the superior and inferior arches and supplying the
ision into frontal and parietal branches. eyelids. They anastomose with branches of the supraorbital, zygomatico
orbital and lacrimal arteries. The inferior arch also anastomoses with
Middle temporal artery The middle temporal artery arises just the facial artery.
above the zygomatic arch and perforates the temporal fascia to supply
temporalis. It anastomoses with the deep temporal branches of the External (dorsal) nasal artery The external nasal artery is a termi
maxillary artery. nal branch of the anterior ethmoidal artery, which arises from the
ophthalmic artery. It emerges at the junction of the nasal bone and the
Frontal (anterior) branch The frontal branch passes upwards lateral nasal cartilage and supplies the skin covering the external nose.


towards the frontal tuberosity and supplies the muscles, skin and peri
cranium in this region. It anastomoses with its contralateral fellow and Occipital artery
with the supraorbital and supratrochlear branches of the ophthalmic
artery.
The occipital artery arises in the neck from the external carotid artery
Parietal (posterior) branch The parietal branch is larger than the (see Fig. 29.8). It runs in a groove on the temporal bone, medial to the
frontal branch of the superficial temporal artery. It curves upwards and mastoid process. Accompanied by the greater occipital nerve, the occipi
backwards, remains superficial to the temporal fascia, and anastomoses tal artery enters the back of the scalp by piercing the investing layer of
with its contralateral fellow and with the posterior auricular and occipi deep cervical fascia that connects the cranial attachments of trapezius
tal arteries. and sternocleidomastoid. Tortuous branches run between the skin and
the occipital belly of occipitofrontalis, anastomosing with the opposite
Facial branches of the maxillary artery occipital, posterior auricular and superficial temporal arteries, as well
as with the transverse cervical branch of the subclavian artery. These
branches supply the occipital belly of occipitofrontalis and the skin and
The maxillary artery is the larger of the two terminal branches of the
pericranium associated with the scalp as far forwards as the vertex. The
external carotid artery, and has three branches that supply the face,
artery may give off a meningeal branch, which traverses the parietal
namely: the mental, buccal and infraorbital arteries (see Figs 26.1, 26.2).
foramen.
Mental artery The mental artery arises from the first part of the maxil
Posterior auricular artery
lary artery as a terminal branch of the inferior alveolar artery. It emerges
on to the face from the mandibular canal at the mental foramen, sup
plies muscles and skin in the chin region, and anastomoses with the The posterior auricular artery arises in the neck from the external carotid
inferior labial and submental arteries. artery and ascends between the auricle and mastoid process. It supplies


Face and scalp
500
4
nOITces
the cranial surface of the auricle via its auricular branch, and the occipi Posterior auricular and occipital veins
tal belly of occipitofrontalis and the scalp behind and above the auricle
via its occipital branch. The posterior auricular artery anastomoses with
The posterior auricular vein arises in a parietooccipital network that
the occipital artery.
also drains into tributaries of the occipital and superficial temporal
veins. It descends behind the auricle to join the posterior division of
the retromandibular vein in, or just below, the parotid gland, to form
VEINS
the external jugular vein. It receives a stylomastoid vein and tributaries
from the cranial surface of the auricle, drains the region of the scalp
The veins of the face are subject to considerable variations; the follow
behind the ear and drains into the external jugular vein. The occipital
ing description concerns those that are relatively constant (see Fig.
vein begins in a posterior network in the scalp, pierces the cranial
30.20).
attachment of trapezius, turns into the suboccipital triangle and joins
the deep cervical and vertebral veins. It may be joined by a vein draining
Supratrochlear vein
the diploë in the occipital bone and then passes to either the internal
jugular, posterior auricular, deep cervical or vertebral veins. Emissary
The supratrochlear vein starts on the forehead from a venous network veins connect the occipital vein to the intracranial venous sinuses via
connected to the frontal tributaries of the superficial temporal vein. the mastoid and parietal foramina and through the posterior condylar
Veins from this network form a single trunk that descends to the bridge canal and occipital protuberances.
of the nose, near the midline and parallel with its contralateral fellow.
The veins are joined by a nasal arch across the nose. They then diverge,
each joining a supraorbital vein to form the facial vein near the medial LYMPHATIC DRAINAGE OF THE FACE AND SCALP
canthus of the eye.
Lymph vessels from the frontal region above the root of the nose drain


Supraorbital vein to the submandibular nodes (Fig. 30.21; see Fig. 29.15). Vessels from
the rest of the forehead, temporal region, upper half of the lateral
auricular aspect and anterior wall of the external acoustic meatus drain
The supraorbital vein begins near the zygomatic process of the frontal
to the superficial parotid nodes, which lie just anterior to the tragus,
bone, connecting with branches of the superficial and middle tempor
either on or deep to the parotid fascia. These nodes also drain lateral
al veins. It passes medially above the orbital opening, pierces orbicu
vessels from the eyelids and skin of the zygomatic region, and their
laris oculi and unites with the supratrochlear vein near the medial
efferent vessels pass to the upper deep cervical nodes. A strip of scalp
canthus of the eye to form the facial vein. A branch passes through the
above the auricle, the upper half of the cranial aspect and margin of the
supraorbital notch, where it receives veins from the frontal sinus and
auricle, and the posterior wall of the external acoustic meatus all drain
frontal diploë, and subsequently connects with the superior ophthal
to the upper deep cervical and posterior auricular nodes. The posterior
mic vein.
auricular nodes are superficial to the mastoid attachment of sterno
cleidomastoid and deep to auricularis posterior, and drain to the upper
Facial vein
deep cervical nodes. The auricular lobule, floor of the external acoustic
meatus and skin over the mandibular angle and lower parotid region
The facial vein is the main vein of the face. After receiving the supra all drain to the superficial cervical or upper deep cervical nodes. Super
trochlear and supraorbital veins, it travels obliquely downwards by the ficial cervical nodes lie along the external jugular vein superficial to
side of the nose, passes under zygomaticus major, risorius and sternocleidomastoid. Some efferents pass round the anterior border of
platysma, descends to the anterior border and then passes over the sternocleidomastoid to the upper deep cervical nodes, while others
surface of masseter. It crosses the body of the mandible and runs down


in the neck to drain into the internal jugular vein. The facial vein ini
tially lies behind the more tortuous facial artery but crosses the artery
Posterior auricular nodes
at the lower border of the mandible. The uppermost segment of
the facial vein, above its junction with the superior labial vein, is
Occipital nodes
also called the angular vein; any infection of the mouth or face can
spread via the angular veins to the cavernous sinuses, resulting in
thrombosis.
Tributaries Near its origin, the facial vein connects with the superior
ophthalmic vein, both directly and via the supraorbital vein, and so is
linked to the cavernous sinus. The facial vein receives tributaries from
the side of the nose and, below this, an important deep facial vein from
the pterygoid venous plexus. It also receives the inferior palpebral,
superior and inferior labial, buccinator, parotid and masseteric veins,
and other tributaries that join it below the mandible.
Superficial temporal vein
A widespread venous network across the scalp receives branches from
the supratrochlear, supraorbital, posterior auricular and occipital veins.
Anterior and posterior tributaries from this network unite above the
zygomatic arch to form the superficial temporal vein on each side. The
vein accompanies its artery, usually lying behind it; crosses the posterior
root of the zygoma; and enters the parotid gland, where it joins the
maxillary vein to form the retromandibular vein.
Tributaries The tributaries are the parotid veins, rami draining the
temporomandibular joint, anterior auricular, transverse facial and
middle temporal veins. The middle temporal vein receives the orbital
Submental nodes
vein (formed by the lateral palpebral veins), pierces the temporal fascia
and then passes back between the layers of the fascia to join the super Submandibular nodes To upper deep cervical nodes
ficial temporal vein just above the level of the zygomatic arch.
Pre-auricular and parotid nodes
Buccal, mental and infraorbital veins
Fig. 30.21 The lymphatic drainage of the face and scalp. Arrows indicate
the direction of flow. (From Drake RL, Vogl AW, Mitchell A (eds), Gray’s


The buccal, mental and infraorbital veins drain the cheek and chin Anatomy for Students, 2nd ed, Elsevier, Churchill Livingstone. Copyright
regions and pass into the pterygoid venous plexus. 2010.)


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Fig. 30.22 The cutaneous
innervation of the face and
Ophthalmic nerve [V 1] neck, showing dermatomes
(in bold). (Adapted from
Drake RL, Vogl AW, Mitchell
A (eds), Gray’s Anatomy for
Greater occipital Students, 2nd ed, Elsevier,
Zygomaticotemporal nerves (C2 dorsal ramus) Churchill Livingstone.
Copyright 2010.)
Supratrochlear nerve
Supraorbital nerve
Auriculotemporal nerve
Infratrochlear nerve
Maxillary nerve [V]
2 Greater occipital nerve
External nasal nerve
C3 dorsal ramus
Infraorbital nerve
Lesser occipital nerve
Zygomaticofacial nerve
Lesser occipital
and greater auricular
C4 dorsal ramus
Mental nerve
Greater auricular nerve
Buccal nerve
Transverse cervical nerve
Mandibular nerve [V]
3
Transverse cervical
follow the external jugular vein to the lower deep cervical nodes in the nerve. The fields are not horizontal but curve upwards (Fig. 30.22),
subclavian triangle. apparently because the facial skin moves upwards with growth of the
The occipital region of the scalp drains partly to the occipital nodes, brain and skull. Embryologically, each division of the trigeminal nerve
and partly to a vessel that runs along the posterior border of sterno is associated with a developing facial process that gives rise to a specific
cleidomastoid to the lower deep cervical nodes. Occipital nodes are area of the adult face: the ophthalmic nerve is associated with the
commonly superficial to the upper attachment of trapezius but occa frontonasal process, the maxillary nerve with the maxillary process,
sionally lie in the superior angle of the posterior triangle. and the mandibular nerve with the mandibular process.
There are usually three submandibular nodes, internal to the deep
cervical fascia in the submandibular triangle. One lies at the anterior Ophthalmic nerve
pole of the submandibular gland, and two flank the facial artery as it
reaches the mandible. Other nodes are often embedded in the gland or
The cutaneous branches of the ophthalmic nerve supply the conjunc


deep to it. Submandibular nodes drain a wide area, including vessels
tiva, skin over the forehead, upper eyelid and much of the external
from the submental, buccal and lingual groups of nodes, and their
surface of the nose.
efferents pass to the upper and lower deep cervical nodes. The external
nose, cheek, upper lip and lateral parts of the lower lip drain directly Supratrochlear nerve
to the submandibular nodes; the afferent vessels may have a few buccal The supratrochlear nerve is the smaller terminal branch of the frontal
nodes along their course and near the facial vein. The mucous mem nerve. It runs anteromedially in the roof of the orbit, passes above the
brane of the lips and cheek drains to the submandibular nodes, and trochlea, and supplies a descending filament to the infratrochlear
the lateral part of the cheek drains to the parotid nodes. The central branch of the nasociliary nerve. The nerve emerges between the trochlea
part of the lower lip, buccal floor and tip of the tongue all drain to the and the supraorbital foramen at the frontal notch, curves up on the
submental nodes, which lie on mylohyoid between the anterior bellies forehead close to the bone with the supratrochlear artery, and supplies
of the digastric muscles. These nodes receive afferents bilaterally, some the conjunctiva and the skin of the upper eyelid. It then ascends beneath
decussating across the chin; their efferents pass to the submandibular the corrugator and the frontal belly of occipitofrontalis before dividing
and juguloomohyoid nodes. into branches that pierce these muscles to supply the skin of the lower
forehead near the midline.
INNERVATION Supraorbital nerve
The supraorbital nerve is the larger terminal branch of the frontal nerve.
The numerous muscles of facial expression are supplied by the facial It traverses the supraorbital notch or foramen and supplies palpebral
nerve, while the two muscles of mastication that relate to the face are filaments to the upper eyelid and conjunctiva. It ascends on the fore


innervated by the mandibular division of the trigeminal nerve. The head with the supraorbital artery, and divides into medial and lateral
sensory innervation is primarily from the three divisions of the trigem branches that supply the skin of the scalp nearly as far back as the
inal nerve, with smaller contributions from the cervical spinal nerves. lambdoid suture. These branches are at first deep to the frontal belly of
The detailed innervation of the auricle is considered on page 629. occipitofrontalis. The medial branch perforates the muscle to reach the
skin, while the lateral branch pierces the epicranial aponeurosis.
TRIGEMINAL NERVE Lacrimal nerve
The lacrimal nerve is the smallest of the main ophthalmic branches and
Three large areas of the face can be mapped out to indicate the periph pierces the orbital septum to end in the lateral region of the upper
eral nerve fields associated with the three divisions of the trigeminal eyelid, which it supplies. It anastomoses with filaments of the facial


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nerve. Occasionally, it is absent, in which case it is replaced by the Auriculotemporal nerve
zygomaticotemporal nerve; the relationship is reciprocal, and when
The auriculotemporal nerve emerges on to the face behind the tem
the zygomaticotemporal nerve is absent it is replaced by a branch of
poromandibular joint within the superior surface of the parotid gland.
the lacrimal nerve.
It ascends posterior to the superficial temporal vessels, passes over the
posterior root of the zygoma, and divides into superficial temporal
Infratrochlear nerve
branches (see Figs 32.20, 32.25). The cutaneous branches of the auric
The infratrochlear nerve branches from the nasociliary nerve. It leaves
ulotemporal nerve supply the tragus and part of the adjoining auricle
the orbit below the trochlea and supplies the skin of the eyelids, the
of the ear and the posterior part of the temple. The nerve may be
conjunctiva, lacrimal sac, lacrimal caruncle and the side of the nose
damaged during parotid gland surgery, resulting in impaired sensation
above the medial canthus.
of the tragus and temple. It communicates with the temporofacial divi
External nasal nerve sion of the facial nerve, usually by two rami that pass anterolaterally
behind the neck of the mandible. These communications anchor the
The external nasal nerve is the terminal branch of the anterior ethmoi
facial nerve close to the lateral surface of the condylar process of the
dal nerve. It descends through the lateral wall of the nose and supplies
mandible and limit its mobility during surgery. Communications with
the skin of the nose below the nasal bones, excluding the alar portion
the temporal and zygomatic branches of the facial nerve loop around
around the external nares.
the transverse facial and superficial temporal vessels.
Maxillary nerve
FACIAL NERVE
The maxillary nerve passes through the orbit to supply the skin of the
lower eyelid, the prominence of the cheek, the alar part of the nose,
part of the temple, and the upper lip. It has three cutaneous branches: The facial nerve emerges from the base of the skull at the stylomastoid


the zygomaticotemporal, zygomaticofacial and infraorbital nerves. foramen and almost immediately gives off the nerves to the posterior
belly of digastric and stylohyoid, and the posterior auricular nerve,
Zygomaticotemporal nerve which supplies the occipital belly of occipitofrontalis and some of the
The zygomaticotemporal nerve traverses a canal in the zygomatic bone auricular muscles (Fig. 30.23).
and emerges into the anterior part of the temporal fossa, where it The nerve next enters the parotid gland high up on its posteromedial
ascends between the bone and temporalis before piercing the temporal surface and passes forwards and downwards behind the mandibular
fascia about 2 cm above the zygomatic arch to supply the skin of the ramus. Within the substance of the gland, it branches into superior
temple. It communicates with the facial and auriculotemporal nerves. (temporofacial) and inferior (cervicofacial) trunks, usually just behind
As it pierces the deep layer of the temporal fascia, it sends a slender and superficial to the retromandibular vein. The trunks branch further
twig between the two layers of the fascia towards the lateral angle of to form a parotid plexus (pes anserinus). Five main terminal branches
the eye. It was thought that the branch carried parasympathetic post arise from the plexus; they diverge within the gland and leave by its
ganglionic fibres from the pterygopalatine ganglion to the lacrimal anteromedial surface, medial to its anterior margin, to supply the
gland; it is now believed that these fibres innervate the lacrimal gland muscles of facial expression (see Fig. 30.23). Six distinctive anastomotic
directly. patterns were originally classified by Davis et al (1956) and these are
illustrated in Figure 30.24. Numerous microdissection studies have
Zygomaticofacial nerve demonstrated that branching patterns and anastomoses between
The zygomaticofacial nerve traverses the inferolateral angle of the orbit branches, both within the parotid and on the face, exhibit considerable


and emerges on the face through a foramen in the zygomatic bone. It individual variation (e.g. Lineaweaver et al 1997, Kwak et al 2004); the
perforates orbicularis oculi to supply the skin on the prominence of the account that follows is therefore an overview. In surgical terms, these
cheek and forms a plexus with zygomatic branches of the facial nerve anastomoses are important, and presumably explain why accidental or
and palpebral branches of the maxillary nerve. Occasionally, the nerve deliberate division of a small branch often fails to result in the expected
is absent. facial nerve weakness. The surface anatomy of the facial nerve is
described on page 412.
Infraorbital nerve The temporal branch usually divides into anterior and posterior rami
The infraorbital nerve emerges on to the face at the infraorbital foramen, soon after piercing the parotidomasseteric fascia below the zygomatic
where it lies between levator labii superioris and levator anguli oris. It arch; there is often a middle (frontal) ramus. These rami cross the arch
gives off palpebral, nasal and superior labial branches. The palpebral in subcutaneous tissue and above the arch lie in the subgaleal space,
branches ascend deep to orbicularis oculi, pierce the muscle to supply where their course is extremely variable. Twigs supply intrinsic muscles
the skin in the lower eyelid, and join with the facial and zygomatico on the lateral surface of the auricle, and the anterior and superior
facial nerves near the lateral canthus. Nasal branches supply the skin of auricular muscles, and communicate with the zygomaticotemporal
the side of the nose and of the movable part of the nasal septum, and branch of the maxillary nerve and the auriculotemporal branch of the
join the external nasal branch of the anterior ethmoidal nerve. Superior mandibular nerve. The more anterior branches supply the frontal belly
labial branches, which are large and numerous, descend behind levator of occipitofrontalis, orbicularis oculi and corrugator, and join the
labii superioris to supply the skin of the anterior part of the cheek and supraorbital and lacrimal branches of the ophthalmic nerve.


upper lip. They are joined by branches from the facial nerve to form Zygomatic branches are generally multiple. They cross the zygomatic
the infraorbital plexus. The infraorbital nerve is commonly implicated bone to the lateral canthus of the eye and supply orbicularis oculi; they
in trigeminal neuralgia, and is amenable to cryotherapy where medical may also supply muscles innervated by the buccal branch. Twigs com
therapy fails. municate with filaments of the lacrimal nerve and the zygomaticofacial
branch of the maxillary nerve.
Mandibular nerve The buccal branch is usually single. It has a close relationship to the
parotid duct for about 2.5 cm after emerging from the parotid gland,
and typically lies below the duct. Superficial branches run beneath the
The mandibular nerve supplies skin over the mandible, the lower lip,
subcutaneous fat and superficial musculoaponeurotic system (SMAS).
the fleshy part of the cheek, part of the auricle of the ear and part of
Some branches pass deep to procerus and join the infratrochlear and
the temple via the buccal, mental and auriculotemporal nerves.
external nasal nerves. Upper deep branches supply zygomaticus major
Buccal nerve and levator labii superioris, and form an infraorbital plexus with the
The buccal nerve emerges on to the face from behind the ramus of the superior labial branches of the infraorbital nerve. They also supply
mandible and passes laterally in front of masseter to unite with the levator anguli oris, zygomaticus minor, levator labii superioris alaeque
buccal branches of the facial nerve. It supplies the skin over the anterior nasi and the small nasal muscles; these branches are sometimes
part of buccinator. described as lower zygomatic branches. Lower deep branches supply
buccinator and orbicularis oris; they communicate with filaments of the
Mental nerve
buccal branch of the mandibular nerve.
The mental nerve is the terminal branch of the inferior alveolar nerve. There are usually two marginal mandibular branches. They run for
It enters the face through the mental foramen, where it is directed wards towards the angle of the mandible under platysma, and then turn


backwards, and supplies the skin of the lower lip and labial gingivae. upwards across the body of the mandible to pass under depressor anguli
Occasionally, the mental nerve is important aetiologically in the pain oris. The branches supply risorius and the muscles of the lower lip and
of trigeminal neuralgia, and it is amenable to cryotherapy surgery. chin, and filaments communicate with the mental nerve. The marginal


Innervation
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A B
External acoustic Temporal branches
meatus
Posterior auricular Zygomatic branches
nerve
Facial nerve Posterior auricular nerve
Mastoid process
Temporofacial branch Temporofacial branch
Cervicofacial branch Digastric branch Cervicofacial branch
Posterior belly of Parotid gland
digastric
Mandible
Buccal branches
Marginal mandibular
branches
Cervical branches
Fig. 30.23 The distribution of the facial nerve. A, The branches given off immediately after the nerve exits the stylomastoid foramen. B, The branches of
the nerve on the face. (From Drake RL, Vogl AW, Mitchell A (eds), Gray’s Anatomy for Students, 2nd ed, Elsevier, Churchill Livingstone. Copyright 2010.)
1 1
2 2
1
2 3
3 3 II
IV
3
4
4
5
VI
5
4 1
1
1
2
5
2
2
I
3
V 3
III 3
4
4
5
I Type I, 13% 1 temporal branch 5
4
II Type II, 20% 2 zygomatic branch
III Type III, 28% 3 buccal branch 5
IV Type IV, 24% 4 mandibular branch
V Type V, 9% 5 cervical branch
VI Type VI, 6%
Fig. 30.24 The pattern of branching of the facial nerve. (Modified with permission from Berkovitz BKB, Moxham BJ 2002 Head and Neck Anatomy.
London: Martin Dunitz, and from Davis RA, Anson BJ, Budinger JM, Kurth IE 1956 Surgical anatomy of the facial nerve and parotid gland based upon a
study of 350 cervicofacial halves. Surg Gynecol Obstet 102:385–412, with permission from the American College of Surgeons.)
mandibular branch has an important surgical relationship with the Lesions of the facial nerve
lower border of the mandible. Facial paralysis may be due to an upper motor neurone lesion (when


The cervical branch emerges from the lower part of the parotid gland frontalis is partially spared because of the bilateral innervation of the
and runs anteroinferiorly under platysma to the front of the neck. Typi muscles of the upper part of the face) or a lower motor neurone lesion
cally single, it supplies platysma and communicates with the transverse (when all branches may be involved). Ipsilateral lower motor neurone
cutaneous cervical nerve. facial paralysis is most commonly idiopathic (Bell’s palsy). There are a
Cutaneous branches of the facial nerve accompany the auricular large number of other recognized causes, including geniculate herpes
branch of the vagus; they are believed to innervate the skin on both zoster (Ramsay Hunt syndrome) and tumours of the parotid and tem
auricular aspects, in the conchal depression and over its eminence. poral bone; sadly, a number are the iatrogenic results of parotid and


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Lateral ligament, Superficial temporal Fig. 30.25 The principal immediate deep
temporomandibular joint artery relations of the parotid gland. The outline
of the parotid gland is indicated by the
Masseter, middle layer Superficial temporal vein interrupted black line.
Maxillary vein
Facial nerve
Masseter, superficial layer
Maxillary artery Styloid process
Parotid duct
Accessory nerve
External carotid artery
Transverse process
Buccinator of atlas
Retromandibular vein Digastric,
posterior belly
Stylohyoid Posterior auricular vein
Facial vein Accessory
nerve
Submandibular gland
Posterior branch
Facial artery of retromandibular vein
Lingual artery Anterior branch of
retromandibular vein
Hyoglossus
Internal jugular
vein
Occipital artery
Body of hyoid bone External jugular
vein
Superior thyroid artery
Common carotid bifurcation Hypoglossal nerve (Common) facial vein
vestibular schwannoma surgery. Only those muscles innervated by The superficial surface is covered by skin and superficial fascia, which
degenerating or demyelinating branches of the facial nerve become contains the facial branches of the great auricular nerve, superficial
weak. parotid lymph nodes and the posterior border of platysma. It extends
The facial nerve is routinely isolated as part of a superficial parotid upwards to the zygomatic arch, backwards to overlap sternocleidomas
ectomy operation, typically in the treatment of parotid tumours, when toid, downwards to its apex posteroinferior to the mandibular angle,
that part of the gland lying superficial to the plane of the facial nerve and forwards to lie on masseter below the parotid duct.
is removed along with the tumour. Although this can affect all the The anteromedial surface is grooved by the posterior border of the
branches of the facial nerve, the weakness is often confined to the ter mandibular ramus. It covers the posteroinferior part of masseter, the
ritory innervated by the marginal mandibular branch, which is most lateral aspect of the temporomandibular joint and the adjoining part


likely to be stretched during surgical intervention and is manifested by of the mandibular ramus. It passes forwards, medial to the ramus of
a weakness of the lower lip on the affected side. the mandible, to reach medial pterygoid. The gland may therefore be
subdivided into a larger superficial part and a smaller part, the deep
‘lobe’, deep to the ramus, the two being joined by an isthmus. Branches
CERVICAL SPINAL NERVES of the facial nerve emerge on the face from the anterior margin of this
surface.
Cervical spinal nerves have cutaneous branches that supply areas of skin The posteromedial surface is moulded to the mastoid process,
in the face and scalp (see Fig. 30.22). The named branches are the great sternocleidomastoid, posterior belly of the digastric, and the styloid
auricular and lesser occipital nerves, which are part of the cervical plexus process and its associated muscles. The external carotid artery grooves
and are described on page 442 (see Fig. 29.1), and the greater occipital this surface before entering the gland, and the internal carotid artery
nerve, which is described on page 768 (see Figs 43.76, 45.8). and internal jugular vein are separated from the gland by the styloid
process and its associated muscles (Fig. 30.25). The anteromedial and
posteromedial surfaces meet at a medial margin that may project so
PAROTID SALIVARY GLAND
deeply that it contacts the lateral wall of the pharynx.
The paired parotid glands are the largest of the salivary glands. Each has Deep lobe tumours The deep ‘lobe’ of the gland extends behind
an average weight of 25 g and is an irregular, lobulated, yellowish mass, the mandibular ramus, where its deep surface lies immediately lateral
lying largely below the external acoustic meatus between the mandible to the superior constrictor of the pharynx. When a parotid tumour,
and sternocleidomastoid. The gland also projects forwards on to the either benign or malignant, develops in the deep ‘lobe’, the mass


surface of masseter (see Fig. 30.23B). Sometimes, a small, usually presents as a swelling in the lateral wall of the oropharynx and not as
detached, part called the accessory parotid gland (pars accessoria or a facial swelling.
socia parotidis) lies between the zygomatic arch above and the parotid
duct below (Fromer 1977). The overall shape of the parotid gland is
variable. Viewed laterally, in half of cases it is roughly triangular in STRUCTURES WITHIN THE PAROTID GLAND
outline. Sometimes, however, the gland is more or less of even width
throughout, and the upper and lower poles are rounded. The external carotid artery, retromandibular vein and facial nerve
In its usual inverted pyramidal form, the parotid gland presents a (Langdon 1998), either in part or in whole, traverse the gland and
small superior surface, and superficial, anteromedial and posteromedial branch within it. The external carotid artery enters the posteromedial
surfaces. It tapers inferiorly to a blunt apex. The concave superior surface and divides into the maxillary artery, which emerges from the
surface is related to the cartilaginous part of the external acoustic anteromedial surface, and the superficial temporal artery, which gives
meatus and posterior aspect of the temporomandibular joint. Here, the off its transverse facial branch in the gland and ascends to leave its
auriculotemporal nerve curves round the neck of the mandible, embed upper limit (see Fig. 30.23). The posterior auricular artery may also
ded in the capsule of the gland. The apex overlaps the posterior belly branch from the external carotid artery within the gland, leaving by its
of digastric and the carotid triangle to a variable extent. posteromedial surface.


parotid salivary gland
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The retromandibular vein, formed by the union of the maxillary and
superficial temporal veins (which enter near the points of exit of the
corresponding arteries), is superficial to the external carotid artery. It
descends in the parotid gland and emerges behind the apex of the
gland, where it usually divides into an anterior branch, which passes
forwards to join the facial vein, and a posterior branch, which joins the
posterior auricular vein to form the external jugular vein. Occasionally,
it is not connected to the external jugular vein, which is then small, and
the anterior jugular vein is enlarged.
PAROTID CAPSULE
The parotid gland is enclosed within an unyielding parotid capsule
derived from the investing layer of deep cervical fascia. Acute inflam
mation of the parotid gland (acute sialadenitis) may cause exquisite
pain in the preauricular region as a result of stretching of the capsule
and stimulation of the great auricular nerve. The pain is usually exacer
bated at mealtimes when the gustatory stimulus to the gland results in
further turgor within the capsule. Causes of acute sialadenitis include
parotid duct obstruction (calculus, mucus plug and duct stricture) and Fig. 30.26 An oblique lateral radiograph showing a normal parotid duct
mumps. outlined after injection of radio-opaque contrast medium (sialogram). Note
that here the main duct is formed by the union of three smaller ducts at
the posterior border of the ramus of the mandible. (Courtesy of Dr N
PAROTID DUCT Drage.)
The average dimensions of the parotid duct are 5 cm long and 3 mm
wide (although it is narrower at its oral orifice). It begins by the conflu
ence of two main tributaries within the anterior part of the parotid
gland; the duct appears at the anterior border of the upper part of the VASCULAR SUPPLY AND LYMPHATIC DRAINAGE
gland and passes horizontally across masseter, approximately midway
between the angle of the mouth and the zygomatic arch (see Figs The parotid gland receives its arterial supply from the external carotid


30.18C, 30.25, 31.39). If the duct arises lower down, it may run artery and its branches within and near the gland. The veins drain to
obliquely upwards. It crosses masseter, turns medially at its anterior the external jugular vein via local tributaries.
border at almost a right angle, and traverses the buccal fat pad and Lymph nodes occur in the skin overlying the parotid gland (pre
buccinator opposite the crown of the upper third molar tooth. The duct auricular nodes) and in the substance of the gland. There are usually
then runs obliquely forwards for a short distance between buccinator ten lymph nodes present in the gland; the majority lie in the superficial
and the oral mucosa before it opens on a small papilla opposite the part of the gland above the plane related to the facial nerve. Lymph
second upper molar crown. The submucosal passage of the duct serves from the parotid gland drains to the upper deep cervical lymph nodes.
as a valvular mechanism, preventing inflation of the gland with raised
intraoral pressures. While crossing masseter, the duct lies between the
upper and lower buccal branches of the facial nerve, and may receive INNERVATION
the accessory parotid duct.
The accessory part of the gland (Fromer 1977) and the transverse Preganglionic nerves travel in the lesser petrosal branch of the glos
facial artery lie above the parotid duct; the buccal branch of the man sopharyngeal nerve and synapse in the otic ganglion (Ch. 32 and see
dibular nerve, emerging from beneath temporalis and masseter, lies just Fig. 26.7). Postganglionic secretomotor fibres reach the gland via the
below, at the anterior border of masseter. The parotid duct may be auriculotemporal nerve.
crossed by anastomosing branches between the zygomatic and buccal
branches of the facial nerve. Gustatory sweating (Frey’s syndrome or auriculotemporal
The ramifications of the ductal systems, and their patterns and cali syndrome) Gustatory sweating (auriculotemporal syndrome) com
bres, can be demonstrated radiographically by injecting a radioopaque monly develops after parotid surgery or other surgery or trauma that


substance into the parotid duct via a cannula. In a lateral parotid sialo results in opening of the parotid capsule. It is thought to reflect aberrant
gram, the main duct can be seen to be formed near the centre of the innervation of sweat glands on the face by regrowing parasympathetic
posterior border of the mandibular ramus by the union of two or three secretomotor axons that would previously have innervated the parotid
ducts that ascend or descend, respectively, at right angles to the main gland. Frey’s syndrome is characterized by sweating, warmth and
duct. As it crosses the face, the main duct also receives from above five redness of the face as a result of salivary stimulation by the smell or
or six ductules from the accessory parotid gland (Fig. 30.26). As it taste of food. The management of Frey’s syndrome is difficult. Denerv
curves round the anterior border of masseter, it is often compressed and ation by tympanic neurectomy or auriculotemporal nerve avulsion has
its shadow is attenuated. Deep lacerations of the cheek, where the been advocated but is often not curative. The symptoms can be managed
integrity of the parotid duct is in doubt, should be explored and by the subcutaneous infiltration of purified botulinum toxin into the
repaired using microsurgical techniques, to prevent saliva leaking into affected area and use of antiperspirant.
the soft tissues of the cheek and subsequent sialocele formation. Microstructure of the salivary glands is described in Chapter 31.


Face and scalp
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Bonus e-book images and videos
Fig. 30.10 A compound craniofacial fracture Fig. 30.14 A typical left zygomatic fracture. through a transconjunctival incision, with
with disruption of the anterior and posterior lateral cantholysis; the position was checked
walls of the frontal sinus, torn dura, and Fig. 30.15 Image fusion of computed with intraoperative navigation.
intracranial bone. tomography and magnetic resonance
imaging, showing an extensive left medial Video 30.1 Pan-facial fractures.
wall fracture.
Fig. 30.11 An extended naso-orbito-ethmoid
(NOE) fracture. Video 30.2 Postoperative cranio-orbital
Fig. 30.16 A, A typical large medial wall and
imaging.
floor fracture. The bone here, the lamina
Fig. 30.12 A typical high-energy pan-facial
papyracea, is the thinnest in the orbit. The
injury. intact medial wall on the right side is Video 30.3 A comminuted zygomatic
outlined in green. B, In this case, the intact fracture (plus Le Fort I) pattern.
Fig. 30.13 Various examples of plating right medial wall (green line) was mirrored;
configurations and titanium alloplastic the red line outlines the defect on the left Video 30.4 A comminuted zygomatic
reconstructions. orbit. C, A titanium plate was then placed fracture pattern – post reduction.
KEY REFERENCES
Ahmas F, Kirkpatrick NA, Lyne J et al 2006 Buckling and hydraulic mecha Le Fort R 1901 Etude expérimental sur les fractures de la mâchoire supérieure.
nisms in orbital blowout fractures: fact or fiction. J Craniofac Surg Rec Chir Paris 23:208–27.
17:438–41. A paper that represents the standard way of describing maxillary fractures.
A paper that does for orbital injuries what Le Fort did for maxillary injuries. Le Fort’s classification has endured and still resonates in clinical practice.
The contribution of anatomy to the pathogenesis of floor and medial orbital
Loukota RA, Eckelt U, De Bont L et al 2005 Subclassification of fractures of
fractures is elegantly shown.


the condylar process of the mandible. Br J Oral Maxillofac Surg 43:
Borges AF, Alexander JE 1962 Relaxed skin tension lines, Zplasties on scars, 72–3.
and fusiform excision of lesions. Br J Plast Surg 15:242–54. A very brief paper that is superb in its simplicity, presenting a logical and
A paper that provides the anatomical basis for every incision made on the pragmatic approach to classifying these injuries, and signposting both
face. surgical difficulty and approach.
Eljamel M, Foy P 1990 Posttraumatic CSF fistulae: the case for surgical Mitz V, Peyronie M 1976 The superficial musculoaponeurotic system
repair. Br J Neurosurg 4:479–83. (SMAS) in the parotid and cheek area. Plast Reconstruct Surg 58:
A paper that provides the clinical evidence for management of fractures of 80–8.
the anterior skull base. A paper that provides the anatomical basis for all invasive aesthetic and
reconstructive facelift surgery.
Gillies HD, Kilner TP, Stone D 1927 Fractures of the malar–zygomatic com
pound: with a description of a new Xray position. Br J Surg 14:651–6. Ziarah HA, Atkinson ME 1981 The surgical anatomy of the mandibular
An old paper but the technique described is a very practical application of distribution of the facial nerve. Br J Oral Surg 19:159–70.
exploiting the anatomy of the temporal fossa. The use of temporalis to glide An outline of how the mandibular branch of the facial nerve is at risk in all
the elevator down to below the arch is insightful. incisions at the lower border of the mandible, in submandibular gland
excision, incision of space-occupying dental infections, and neck dissection.
Langdon JD 1998 Parotid surgery. In: Langdon JD, Patel MF (eds) Operative
A detailed knowledge of this structure is essential.
Maxillofacial Surgery. London: Chapman & Hall; pp. 381–90.
A detailed account of the procedures for the safe dissection of the
intraparotid part of the facial nerve.


SUBSECTION: Upper aerodigestive tract
CHAPTER
31
Oral cavity
The mouth or oral cavity extends from the lips and cheeks externally to Few structural landmarks are visible. The parotid duct drains into
the anterior pillars of the fauces internally, where it continues into the the cheek opposite the maxillary second molar tooth at a small parotid
oropharynx. The mouth can be subdivided into the vestibule external papilla. A hyperkeratinized line (the linea alba) may be seen at a posi
to the teeth and the oral cavity proper internal to the teeth (Fig. 31.1). tion related to the occlusal plane of the teeth. In the retromolar region,
The palate forms the roof of the mouth and separates the oral and nasal a fold of mucosa containing the pterygomandibular raphe extends from
cavities. The floor of the mouth is formed by the mylohyoid muscles the upper to the lower alveolus. The entrance to the pterygomandibular
and is occupied mainly by the tongue. The lateral walls of the mouth space (which contains the lingual and inferior alveolar nerves) lies
are defined by the cheeks and retromolar regions. Three pairs of major lateral to this fold and medial to the ridge produced by the anterior
salivary glands (parotid, submandibular and sublingual) and numerous border of the ramus of the mandible; this is the site for injection for an
minor salivary glands (labial, buccal, palatal, lingual) open into the inferior alveolar nerve block, commonly used to anaesthetize the ipsi
mouth. The muscles in the oral cavity are associated with the lips, lateral lower teeth and gums.
cheeks, floor of the mouth and tongue. The muscles of the lips and
cheeks are described with the face in Chapter 30. The muscles of the Vascular supply and innervation
soft palate are described with the pharynx in Chapter 34 (Berkovitz and
Moxham 2002).
The cheek receives its arterial blood supply principally from the buccal
The mouth is concerned primarily with the ingestion and masti
branch of the maxillary artery, and is innervated by cutaneous branches
cation of food, which is mainly the function of the teeth. The mouth