Muscles of face , neck and tongue with recent advances in the field.

1. TOPIC FOR THE SEMINAR
MUSCLES OF FACE, NECK AND TONGUE
Under the guidance of
Respected Dr. C S Bal
Presented By
HARSHDEEP SINGH
29TH JULY 2013

2. MUSCLES OF FACE, NECK AND TONGUE
1. INTRODUCTION
2. DEVELOPMENT
1. MUSCLES OF FACE
2. MUSCLES OF NECK
3. MUSCLES OF TONGUE
3. DETAILED ANATOMY AND MORPHOLOGY :
1. THE MUSCLES OF FACE
2. MUSCLES OF NECK AND
3. MUSCLES OF TONGUE
4. EXAMINATION OF THE MUSCLES
5. NERVE SUPPLY , BLOOD SUPPLY AND LYMPHATIC DRAINAGE
6. DISORDERS OF THE MUSCLES OF FACE, NECK AND TONGUE
7. CLINICAL SIGNIFICANCE OF THE KNOWLEDGE OF THE MUSCLES OF FACE NECK AND
TONGUE.
8. RECENT ADVANCES
9. REFERENCES

3. INTRODUCTION
• The Facial muscles are a group of striated muscles innervated by the facial nerve
that , among other things , control facial expression. These muscles are also called
Mimetic muscles.
• The facial muscles are concerned with an array of facial expressions & other
functions.
• These muscles are different from other muscle organizations in lacking of deep
fascia beneath the skin of face.
• Neck connects the head to the trunk . It is a conduit for blood vessels, nerves, and
hollow organs
• To facilitate the seemingly complicated area, the neck is divided into two major
areas, or triangles, by the sternocleidomastoid muscle
• The muscles of the TONGUE are grouped into Extrinsic and Intrinsic groups and
serve to facilitate its movements.

4. DEVELOPMENT OF MUSCLES OF FACE
• During the fourth week of gestation, as the maxillary and mandibular processes of
the first pharyngeal arch are developing and growing an-teriorly, a median bulge
covering the brain enlarges and grows forward. This frontonasal prominence
develops just above the stomadeum.

5. Development of the face illustrating derivatives of embryologic development.
Approximately 8 weeks of development.
Adult. Median nasal process (1). Lateral nasal process (2). Maxillary process
(3). Mandibular process (4).

6. DEVELOPMENT OF MUSCLES OF TONGUE
• The tongue forms in the floor of the pharynx beginning in the 4th week of gestation
, first as a median swelling, the TUBERCULUM IMPAR, bounded by two LATERAL
LINGUAL SWELLINGS.These structures develop on the dorsal aspect of the
mandibular arch.

7. DEVELOPMENT OF MUSCLES OF NECK
• As the branchial apparatus develops, the first and second arches grow in a cranial
to caudal fashion, creating the epipericardial ridge. The epipericardial ridge
contains the mesodermal rudiments of the sternocleidomastoid, trapezius, and
the infrahyoid and lingual musculature. The nerves of the epipericardial ridge are
the hypoglossal and spinal accessory. The proliferation of mesoderm in this area
eventually causes overgrowth and narrowing of the third, fourth, and sixth arches
into an ectodermal pit, known as the cervical sinus of His.

8. MUSCLES OF FACE

9. THE CRANIOFACIAL MUSCLES
They are grouped as:
• 1. Epicranial
• 2. circumorbital and palpebral
• 3. nasal
• 4. buccolabial
The EPICRANIUS is made up of two main parts:
• Occipitofrontalis
• Temporoparietalis

10. 2. CIRCUMORBITAL AND PALPEBRAL MUSCLES
• This group of muscle if composed of the following:
• orbicularis oculi,
• corrugator supercilii,
• and levator palpebrae superioris.
3. NASAL MUSCLES
• The nasal muscle group is composed of the following muscles:
• 1. Procerus
• 2. Nasalis
• 3. Depressor septi
4. BUCCOLABIAL MUSCLES
• The shape of the buccal orifice and the posture of the lips are controlled by a
complex three-dimensional assembly of muscular slips. These include:
• Elevators, retractors, and evertors of the upper lip
• Depressors, retractors, and evertors of the lower lip
• A compound sphincter

11. 1. ELEVATORS, RETRACTORS, AND EVERTORS OF THE UPPER LIP :
• Levator labii superioris alaque nasi, levator labii superioris,zygomaticus
major and minor , levator anguli oris , and risorius
2. DEPRESSORS, RETRACTORS, AND EVERTORS OF THE LOWER LIP :
• Depressor labii inferioris , depressor anguli oris , and
mentalis.
3. A COMPOUND SPHINCTER:
• Orbicularis oris , accessory muscles to the orbicularis oris ,incisivus
superior, and Incisivus inferior.

12. VARIOUS FACIAL EXPRESSIONS AND RELATED MUSCLES

13. THE MUSCLES OF THE TONGUE
MUSCLE ORIGIN INSERTION NERVE
SUPPLY
ACTION
INTRINSIC
MUSCLES
Longitudinal
Transverse
Vertical
EXTRINSIC
MUSCLES
Median septum
and submucosa
Mucous
membrane
Hypoglossal
nerve
Alters shape of
tongue
Genioglossus Superior genial
spine of mandible
Blends with
other muscles of
tongue
Hypoglossal
nerve
Protrudes apex of
tongue through
mouth
Hyoglossus Body and greater
cornu of hyoid
bone
Blends with
other muscles of
tongue
Hypoglossal
nerve
Depresses tongue
Styloglossus Styloid process of
temporal bone
Blends with
other muscles of
tongue
Hypoglossal
nerve
Draws tongue
upward
and backward
Palatoglossus Palatine
aponeurosis
Side of tongue Pharyngeal
plexus
Pulls roots of
tongue
upward and
backward, narrows
oropharyngeal
isthmus

16. • A SUMMARY OF THE ACTIONS OF THE TONGUE
• Protrussion: genioglossus
• Retrussion: hyoglossus, styloglossus, genioglossus
• Depression : genioglossus, hyoglossus
• Elevation : styloglossus
• Shortening : longitudinal intrinsic fibers
• Narrowing : transverse intrinsic fibers
• Flattening : vertical intrinsic fibers

17. REGIONS OF THE NECK
• To facilitate the seemingly complicated area, the neck is
divided into two major areas, or triangles, by the
sternocleidomastoid muscle.
These are:
1. Anterior triangle
- the area anterior to the SCM and below the
inferior border of the mandible
2. Posterior triangle
- the area posterior to the SCM and is limited
posteriorly by the trapezius muscle.

19. ANTERIOR TRIANGLE OF THE NECK
SUBDIVISIONS OF THE ANTERIOR TRIANGLE
• DIGASTRIC TRIANGLE
• CAROTID TRIANGLE
• MUSCULAR OR INFERIOR CAROTID TRIANGLE
• SUBMENTAL TRIANGLE
MUSCLES OF THE ANTERIOR TRIANGLE OF THE NECK
• INFRAHYOID MUSCLES
MUSCLE ORIGIN INSERTION ACTION NERVE SUPPLY
Omohyoid Inferior belly:
Superior border of
the scapula
Superior belly:
Intermediate tendon
Inferior belly:
Intermediate tendon
Superior belly:
Lower border of the
body of the hyoid
bone
Depresses the
hyoid bone and
larynx
Ansacervicalis (APR
of C1, C2, C3)

20. Sternothyroid Manubrium
of the
sternum,
posterior
aspect
Oblique line of
thyroid
cartilage
Depresses the
larynx
Ansacervicalis (APR
of C1, C2, C3)
Thyrohyoid Oblique line
of thyroid
cartilage
Body and
greater horn
of hyoid bone,
lower border
Depresses the
hyoid bone
Thyrohyoid branch of
the hypoglossal
nerve
Sternohyoid Manubrium
of the
sternum,
posterior
aspect
Lower border
of the body of
the hyoid
bone
Depresses the
hyoid bone
and larynx
Ansacervicalis (APR
of C1, C2, C3)

22. • SUPRAHYOID MUSCLES
MUSCLE ORIGIN INSERTION ACTION NERVE SUPPLY
Stylohyoid Styloid process Greater horn of
hyoid bone
Elevates hyoid bone Facial nerve
Digastric
(Posterior belly)
Digastric notch of
the temporal bone
at the base of the
skull
Intermediate
tendon
Raises the hyoid
bone
Facial nerve
Digastric
(anterior belly)
Intermediate
tendon
Digastric fossa of
the mandible
Elevates the hyoid
bone
Nerve to the
mylohyoid muscle
Mylohyoid Mylohyoid line on
the medial aspect
of mandibular
body
Median raphe and
body of hyoid
Elevates the hyoid
bone, base of the
tongue, and floor
of the mouth
Nerve to mylohyoid
muscle
Geniohyoid muscle Inferior border
genial tubercle of
the mandible
Body of hyoid bone Elevates hyoid
bone, protracts
hyoid bone
APR of C1

23. THE POSTERIOR TRIANGLE OF THE NECK
SUBDIVISIONS OF THE POSTERIOR TRIANGLE :
• OCCIPITAL TRIANGLE
• SUPRACLAVICULAR TRIANGLE

24. MUSCLE ORIGIN INSERTION ACTION NERVE
Platysma Superficial fascia of
the deltoid and
pectoral regions
Inferior border of
the mandible,
some fibers sweep
upward and blend
with risorius
Stretches tight the
skin of the neck,
depresses the
mandible
Facial nerve
Splenius capitis Lower part of the
ligamentum
nuchae, lower
cervical spines
Mastoid process
and the superior
nuchal line
Bilateral:
Extends the head
Individual:
Flexes the head
laterally
Cervical spinal
nerves
Levator scapulae Transverse
processes of C1 to
C4
Superior portion of
the vertebral
border of the
scapula
Elevates and
rotates the scapula
Dorsal scapular
nerves
Scalenius posterior Transverse
processes of C5
and C6
Superior aspect of
the second rib
Flexes the neck APR of C5 to C8
Scalenius Medius Transverse
processes of C2 to
C7
Superior aspect of
the first rib
Flexes the neck APR of C3 and C4
Scalenius anterior Transverse
processes of C3 to
C6
Scalene tubercle of
the first rib
Participates in
forced inspiration
by elevating the
ribs and sternum
APR of C5 to C8
MUSCLES OF THE POSTERIOR TRIANGLE OF THE NECK

25. BLOOD SUPPLY, NERVE SUPPLY AND LYMPHATIC DRAINAGE OF
THE MUSCLES OF FACE
• VEINS, ARTERIES, AND LYMPHATICS OF THE FACE
• The physiology of the human face is complex. A series of arteries and veins provide
circulation of blood to the various tissues of the face and also the face includes some
lymphatic tissues.
The following are the major arteries of the face :
• Supratrochlear artery
• Supraorbital artery
• Mental artery
• Transverse facial artery
• Zygomaticoorbital artery
• Facial artery
• Submental artery
• Inferior labial
• Superior labial artery
• Lateral nasal artery
• Angular artery
• Occipital artery
• Posterior auricular artery:
• Maxillary artery
• Inferior alveolar artery
• Infraorbital artery
• Superficial temporal artery:

27. IMPORTANT VEINS IN THE FACE INCLUDE THE FOLLOWING:
• Angular vein
• Facial vein
• Maxillary vein
• Superficial temporal vein
• Retromandibular vein
• Posterior auricular vein
• Supraorbital and supratrochlear veins
LYMPHATIC NODES ARE CATEGORIZED INTO SEVERAL GROUPS:
• Submental lymph nodes
• Submandibular lymph nodes
• Parotid lymph nodes

29. NERVE SUPPLY OF MUSCLES OF FACE
• The facial nerve is the seventh (VII) of twelve paired cranial nerves
• The main function of the facial nerve is motor control of most of
the muscles of facial expression. It also innervates the posterior belly of
the digastric muscle, the stylohyoid muscle, and the stapedius muscle of
the middle ear.
• . It emerges from the brainstem between the pons and the medulla, and
controls the muscles of facial expression, and functions in the conveyance
of taste sensations from the anterior two-thirds of the tongue and oral
cavity

31. BLOOD SUPPLY , NERVE SUPPLY AND LYMPHATIC DRAINAGE OF
THE MUSCLES OF TONGUE
Blood supply.
• The main artery is the lingual artery , a branch of the external carotid. It
is accompanied by lingual veins. The deep lingual vein (or ranine vein) can
be seen in the floor of the mouth at the side of the frenulum. The various
veins of the tongue drain ultimately into the internal jugular.
Lymphatic drainage.
• The drainage is to the submental, submandibular, and deep cervical
nodes, and extensive communications occur across the median plane.
Sensory innervation
• The anterior two thirds of the tongue is supplied by (1) the lingual nerve
(of the mandibular nerve) for general sensation and by (2) the chorda
tympani (a branch of the facial nerve that runs in the lingual nerve) for
taste. The posterior third of the tongue and the vallate papillae are
supplied by the glossopharyngeal nerve for both general sensation and
taste. The nerves for taste are cranial nerves VII, IX, and X. The internal
branch of the vagus is responsible for general sensation and taste near the
epiglottis.

34. BLOOD SUPPLY ,NERVE SUPPLY AND LYMPHATIC
DRAINAGE OF MUSCLES OF NECK
Blood Supply to the Neck
• The neck and head is mainly supplied by the common carotid
artery.
Branches of the external carotid artery:
• Superior thyroid artery
• Ascending pharyngeal artery
• Lingual artery
• Facial artery
• Occipital artery
• Posterior auricular artery
• Maxillary artery
• Superficial temporal artery
Venous Drainage of the Head and Neck
• The maxillary, superficial temporal, posterior auricular and occipital
veins all drain into the external jugular veins
• The facial vein drains into the internal jugular veins

37. • Nerves of the Neck
• Both the cervical plexus and the accessory nerve (CN XI) emerge
from the posterior neck triangle.
• The cervical nerve plexus is a plexus of the ventral rami of the first
four cervical spinal nerves which are located from C1 to C4 cervical
segment in the neck.
• Nerves formed from the cervical plexus innervate the back of the
head, as well as some neck muscles.
• The branches of the cervical plexus emerge from the posterior
triangle at the nerve point, a point which lies midway on the
posterior border of the Sternocleidomastoid.
• The accessory nerve is a nerve that controls specific muscles of the
neck, it nerve provides motor innervation from the central nervous
system to the Sternocleidomastoid muscle and the Trapezius
muscle.

39. Lymphatics of the Neck
- Deep Lymph Nodes
• Submental
• Submandibular
- Anterior Cervical Lymph Nodes (Deep)
• Prelaryngeal
• Thyroid
• Pretracheal
• Paratracheal
- Deep Cervical Lymph Nodes
• Lateral jugular
• Anterior jugular
• Jugulodigastric
- Inferior Deep Cervical Lymph Nodes
• Juguloomohyoid
• Supraclavicular

40. CLINICAL EXAMINATION OF MUSCLES OF FACE
• A thorough head and neck examination is paramount, with occasional use
of tests for salivation, tearing, and taste; these are the first steps in
determining the site of injury. Physical examination findings reveal
affected facial musculature movement.
• Tests for facial innervation include the following:
• Forehead wrinkling (frontalis muscle)
• Eye closure (orbicularis oculi muscle)
• Wide smile
• Whistling
• Blowing (eg, buccinator muscle, orbicularis oris muscle, zygomatic muscle)
House-Brackmann scale
• Clinically, injury to the infratemporal facial nerve can be classified by
degree. Multiple classifications of facial nerve injury are found in the
literature. The most frequently used is the House-Brackmann scale

41. HOUSE-BRACKMANN CLASSIFICATION OF FACIAL FUNCTION
Grade Characteristics
I. Normal Normal facial function in all areas
II. Mild dysfunction Slight weakness noticeable on close inspection
May have slight synkinesis
At rest, normal symmetry and tone
Motion
Forehead - Moderate to good function
Eye - Complete closure with minimal effort
Mouth - Slight asymmetry
III. Moderate dysfunction Obvious but not disfiguring difference between sides
Noticeable (but not severe) synkinesis, contracture, or hemifacial spasm
At rest, normal symmetry and tone
Motion
Forehead - Slight to moderate movement
Eye - Complete closure with effort
Mouth - Slightly weak with maximum effort
IV. Moderately severe
dysfunction
Obvious weakness and/or disfiguring asymmetry
At rest, normal symmetry and tone
Motion
Forehead - None
Eye - Incomplete closure
Mouth - Asymmetrical with maximum effort
V. Severe dysfunction Only barely perceptible motion
At rest, asymmetry
Motion
Forehead - None
Eye - Incomplete closure
Mouth - Slight movement
VI. Total paralysis No movement

42. CLINICAL EXAMINATION OF THE MUSCLES OF TONGUE
• Weakness of the tongue manifests itself as a slurring of speech. The
patient complains that their tongue feels "thick", "heavy", or "clumsy."
• Lingual sounds (i.e., l's, t's, d's, n's, r's, etc.) are slurred and this is obvious
in conversation even before direct examination.
• Examination of the tongue first involves observation for atrophy and
fasciculationsAtrophy and fasciculations in combination suggest disease or
damage to the motor neurons of the brain stem, but can be seen with
peripheral nerve damage as well.
• Fasciculations are fine, random, multifocal twitches of muscle. They are
evaluated by observing the tongue while it is at rest in the floor of the
mouth. They are best seen along the lateral aspect of the tongue.
• Protrusion frequently causes a fine tremor in the normal tongue, which
can obscure or mimic fasciculations. Simply having the patient protrude
their tongue in the midline tests strength of the tongue
• A repetitive or complex lingual sound (e.g., "la la la la" or "Methodist
artillery") often shows impediment when any part of the vocal apparatus
is affected (e.g., Broca's region, motor cortex, basal ganglia, cerebellum,
brain stem, nucleus, or nerve).

43. CLINICAL EXAMINATION OF THE MUSCLES OF NECK
• When examining the SCM muscle, the bulk and outline of the muscle
should be observed. Atrophy is common in damage to the nerve and
fasciculations may be seen especially if the motor neurons are diseased.
• The SCM muscle rotates the head away from the side of contraction.
Testing entails having the subject turn their head against the examiner's
hand, which is pressed against the patient's chin . The bulk of the muscle
is then easily seen and palpated, and its strength can be determined.
• A, testing of right sternomastoid muscle. B, testing upper portion of trapezius muscles.

44. • Paralysis of this muscle will produce weakness, although not complete loss
of ability to rotate the head away from the lesion
• .The two sternocleidomastoids contracting together will flex the head
toward the chest. Bilateral weakness may prevent the patient from lifting
their head off a pillow and the head may be inclined posteriorly for lack of
flexor tone
• The spinal accessory nerve innervates the trapezius muscles, which
elevate the shoulders and rotate the scapula upward during abduction of
the arm.
• Denervation is evidenced by atrophy and often fasciculations. The
shoulder droops on the side of the weak muscle and there is downward
displacement of the scapula posteriorly.
• Shrugging the shoulders against resistance is the standard way of testing
the upper trapezius

45. CLINICAL SIGNIFICANCE OF THE KNOWLEDGE OF THE MUSCLES
OF FACE NECK AND TONGUE
• A patient who has damage to the muscles of the head and neck region may have
various issues, which may in turn affect the management of dental hygiene
treatment.
• The cervical muscles change the way in which a patient’s head and neck are
positioned. The patient may not have the ability to place his/her body in a
traditional or ergonomically correct position for the dentist
• The muscles of facial expression give an individual the ability to laugh, cry, smile,
and frown. Damage to these muscles, which would impact these basic functions,
could bring about inconvenience and distress to a patient. As the patient’s oral
health-care provider, the Dentist must be aware of this and handle the situation
with sensitivity
• .An injury to the muscles of facial expression may lead to abnormal movements of
this region. Twitching, spasm, weakness, or paralysis would not be
uncommon. The patient may experience altered taste sensation and dryness of the
mouth.
• If a patient does not have the ability to close his/her lips, he/she may experience
excessive drooling. A familiar cause of facial weakness is Bell’s pal
• The hyoid muscles and the muscles of the tongue will impact the patient’s ability
to properly masticate, swallow, speak, and position his/her tongue. The tongue
may become atrophied in severe cases. A dentist must allow the patient to
communicate to the best of his/her ability. This may take additional time. The
dentist must also consider the tongue’s position when doing procedures such as
taking impressions.

46. DISORDERS OF MUSCLES OF FACE NECK AND TONGUE
• BELL’S PALSY – A form of temporary facial paralysis, Bell's palsy results from
damage or trauma to one of the two facial nerves and is the most common cause
of facial paralysis, Bell's palsy affects only one of the paired facial nerves and one
side of the face.
• HEMIFACIAL SPASM – Hemifacial spasm is a neuromuscular disorder characterized
by frequent involuntary contractions of the muscles on one side of the face. The
first symptom of hemifacial spasm is usually an intermittent twitching of the eyelid
muscle that can lead to forced closure of the eye
• MOTOR NEURON DISEASES – The motor neuron diseases (MNDs) are a group of
progressive neurological disorders that destroy cells that control essential muscle
activity such as speaking, walking, breathing and swallowing
• MUSCULAR DYSTROPHY – the muscular dystrophies (MD) are a group of more
than 30 genetic diseases characterized by progressive weakness and degeneration
of the skeletal muscles that control movement. Symptoms of muscular dystrophy
nerve damage vary with the different types of muscular dystrophy.
• MYASTHENIA GRAVIS – This chronic, autoimmune, neuromuscular disease is
characterized by varying degrees of weakness of the skeletal (voluntary) muscles
of the body. The hallmark symptom of myasthenia gravis is muscle weakness that
increases during periods of activity and improves after periods of rest. The cause
of myasthenia gravis nerve damage is a defect in the transmission of nerve
impulses to muscles.

47. • SPEECH AND LANGUAGE DISORDERS – The inability to form sounds or
articulate words correctly or the inability to comprehend another's
speech.
• TORTICOLLIS is a fixed or dynamic tilt, rotation or flexion of the head
and/or neck. The type of torticollis can be described depending on the
positions of head and neck as
laterocollis : the head is tipped towards the shoulder
rotational torticollis : the head rotates along the longitudal axis
anterocollis : forward flexion of the head and neck
retrocollis : hyperextension of head and neck backward
A multitude of conditions may lead to the development of Torticollis;
including muscular fibrosis, congenital spine abnormalities or toxic or
traumatic brain injury.
• WHIPLASH.
Whiplash often involves pain and stiffness in the neck, but may also
affect the surrounding muscles in your head, mid-back, chest, shoulders, and
arms. Whiplash injuries can be mild or severe, temporary or permanent.
Whiplash is often referred to as “soft tissue injuries,” as the damage is usually
limited to the ligaments, muscles, and tendons of the neck and upper back
and does not involve the fracture of any bones or vertebrae.

48. RECENT ADVANCES
• RECENT PROGRESS IN FACIAL ESTHETIC SURGERY
Rev Stomatol Chir Maxillofac. 1998 Jul;99 Suppl 1:38-71
Recent advances offer a new approach to cosmetic surgery of the frontal, cervico-facial
and orbito-palpebral areas. Conservative frontal lifting procedures displace the entire
frontal muscle (without section or resection) over the underlying bone and periosteal
planes by raising the galea and the antagonist muscles. This repositioning reduces or
eliminate wrinkles by preventing hyperfunction of the frontal muscle. The risk of
sensorial or motor nerve lesions is reduced and the forehead and eyelids have a natural
appearance
• ADVANCES IN FACIAL REANIMATION
Current Opinion in Otolaryngology & Head & Neck Surgery: August 2006 - Volume 14 -
Issue 4
The options for dynamic reanimation of the paralyzed face must be examined in the
context of several patient factors, including age, overall health, and patient desires. The
best functional results asre obtained with direct facial nerve anastomosis and
interpositional nerve grafts. In long-standing facial paralysis, temporalis muscle transfer
gives a dependable and quick result. Microvascular free tissue transfer is a reliable
technique with reanimation potential whose results continue to improve as
microsurgical expertise increases. Postoperative results can be improved with ancillary
soft tissue procedures, as well as botulinum toxin.

49. • ADVANCES IN MUSCLE RECONSTRUCTION OF THE LIP IN THE PRIMARY SURGICAL
TREATMENT OF CLEFT LIP
Hellenic Orthodontic Review. 2008, Vol. 11 Issue 1
• Recently, the improvements of the intrauterine experimental surgery offered a new
perspective for the application of this technique on humans. Fetuses respond to injuries
with a fundamentally different fashion; collagen is deposited in a scarless way by wound
healing during early gestation .This may lead to a more unobstructed growth of the
maxilla. It is assumed that, after an intrauterine repair of a cleft lip and palate,the need
for secondary surgical treatment of the lip and/or the maxilla or for additional
treatments as orthodontic or orthopedic treatment, will be minimal oral most
unnecessary (Papadopoulos et al., 2002a;Papadopulos et al., 2003).Very recently it has
been shown that when bone graft healing takes place following intrauterine surgical
repair of cleft lip and alveolar like defects in sheep fetuses, a tendency of almost normal
maxillary growth can be observed.
• EMG STUDY FOR PERIORAL FACIAL MUSCLES FUNCTION DURING MASTICATION
Journal of Oral Rehabilitation. Mar2008, Vol. 35 Issue 3
• This study aimed to clarify the temporal and quantitative modulation in the orbicularis
oris (OO) and buccinator (BUC) muscle activities during mastication.
• Electromyograms (EMGs) of the facial muscles were recorded with fine wire electrodes
when chewing the chewing gum (one to four sticks) and peanuts (one to five pieces).
Surface EMGs of the masseter (MAS) and digastric muscles were recorded
simultaneously. EMGs of the OO and BUC showed rhythmic single-peaked bursts
corresponding to the jaw-opening phase of chewing cycles.

50. • . The changes of the OO and BUC activities may derive from chewing-generated
sensory inputs in accordance with the physical property of food in part, which
would relate to the function of these muscles during mastication
MASTICATORY FEATURES, EMG ACTIVITY AND MUSCLE EFFORT OF SUBJECTS
WITH DIFFERENT FACIAL PATTERNS
Journal of Oral Rehabilitation. Nov2010, Vol. 37 Issue 11, p813-819
• The aims of this study were to evaluate masticatory performance, mandibular
movement, electromyographic (EMG) activity and muscle effort of masseter and
anterior temporal muscles during mastication. Seventy-eight dentate subjects
were selected and divided into three groups according to vertical facial pattern:
brachyfacial, mesofacial and dolichofacial.Electromyographic activities of masseter
and anterior temporal muscles were evaluated during mastication, and muscle
effort was calculated by the percentage of activity required for mastication based
on maximum muscle effort. It was concluded that the vertical facial pattern
influences masticatory performance, mandibular movement during mastication
and the effort masticatory muscles required for chewing.

51. EFFECTIVENESS OF CIRCUMORAL MUSCLE EXERCISES IN THE DEVELOPING DENTOFACIAL
MORPHOLOGY IN ADENOTONSILLECTOMIZED CHILDREN: AN ULTRASONOGRAPHIC
EVALUATION.
• Journal of the Indian Society of Pedodontics & Preventive Dentistry. Apr2009, Vol. 27 Issue 2, p94-
103
• Alterations in the functions of the facial muscle can establish changes in facial skeleton and in the
development of occlusion. The effect of mouth breathing on the facial morphology is probably
greatest during the growth period. Removal of nasal obstruction, adenoids, and tonsils have not
given beneficial results in the reversion of the habit unless intercepted with various muscle
exercises. Hence, this study was conducted to ultrasonographically evaluate the effectiveness of
circumoral muscle exercises in the developing dentofacial morphology in adenotonsillectomized
children.
• OCCLUSION, STEMOCLEIDOMASTOID MUSCLE ACTIVITY, AND
BODY SWAY
CRANIO: The Journal of Craniomandibular Practice. Jan2006, Vol. 24 Issue 1, p43-49. 7p.
• In normal gravitational conditions, information from the neck and stomatognathic apparatus
play a role in maintaining the body's balance and equilibrium. The current piiot study used
normalgravity conditions to investigate the hypothesis of a functional coupling between
occiusion and neck muscles and body postural oscillations. The immediate effect of modified
occiusal surfaces on the contraction pattern of the sternocieidomastoid muscles during
maximum voluntary cienching and on theoscillation of the center of foot pressure was
analyzed in 11 male astronauts

52. • Occlusal splints were prepared using impressions of their dental arches. The splints
were modeled on the mandibular arch, had only posterior contacts, and were
modified to obtain a more symmetric, standardized contraction of the masseter
and temporalis muscles during teeth clenching. Surface EMG activity of the
stemocleidomastoid muscles was recorded during a maximal voluntary clench with
and without the splint ,A functionally more symmetric maxillo-mandibular position
resulted in a more symmetric sternocieidomastoid muscle contraction pattern and
less body sway. Modifications in the contraction of the masticatory muscles may
therefore affect the whole body

53. REFERENCES
• Clinical Anatomy by Regions by Richard S. Snell 8th edition
• Textbook of Human Anatomy by B.D. Chaurasia 3rd edition
• Textbook of Head and Neck Anatomy by Hiatt and Gartner
• Inderbir S. textbook of Embryology 2nd edition
• Head and Neck Anatomy for Dental Medicine (THIEME Atlas of
Anatomy Series)
• McMinn's Color Atlas of Head and Neck Anatomy, 4e
• Current Opinion in Otolaryngology & Head & Neck Surgery: August
2006 - Volume 14 - Issue 4
• Hellenic Orthodontic Review. 2008, Vol. 11 Issue 1, p35-53.
• Journal of the Indian Society of Pedodontics & Preventive Dentistry.
Apr2009, Vol. 27 Issue 2
• Journal of Oral Rehabilitation. Nov2010, Vol. 37 Issue 11
• CRANIO: The Journal of Craniomandibular Practice. Jan2006, Vol. 24
Issue 1