ANATOMY OF
PHARYNX AND LARYNX AND
APPLIED ASPECTS OF
PHARYNX AND LARYNX
INDIAN DENTAL ACADEMY
Leader in continuing dental ...
contents
Pharynx
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Anatomy
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Development
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Divisions
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Muscles
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Pharyngel tissue spaces
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Innervation
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Arterial supply
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Larynx
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development
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Anatomy

Cartilage

Ligaments
Fibrous membreane

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Joints
Muscles

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Laryngeal cavit...
 Cephalometrics related to pharnyx
 References

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Pharynx

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Fibro muscular tube
Attached to the base of the
skull
Continuous with the
esophagus inferiorly

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Structures of the pharynx
 Has a wall consists of 4 layers
1-mucosa
2-pharyngobasilar fascia
no submucosa,so even slight ...
Development

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Pharyng
eal Arch

Cranial
Nerve

Muscle
derivativ
e

Skeletal
Derivativ
e

1
Mandib
ular

Trigemin
al nerve

Muscle of
mas...
Pharyn
geal
Pouch

Derivative

1

Epithelium of
tympanic cavity and
auditory tube

2

Epithelium of tonsil

3

Inferior pa...
Pharyngeal
(grooves):

Clefts

located
arches

between

these are spaces, thus
contain no germ layer
components
initially ...
Divisions
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nasopharynx
oropharynx
hypopharynx

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Nasopharynx
-extends from the base of the
skull to the soft palate
-functionally a part of the
respiratory system
-remains...
Pharyngeal tonsils
-includes
a-pharyngeal tonsils
b-auditory tube
embedded in the mucosa of
the posterior wall of the
Naso...
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Oropharynx

 extends from the soft palate
above
 to the upper border of epiglottis
below
 at the level of the bodies of...
a- the faucial pillars (arch or fold)
 palatoglosus (anterior),
palatopharyngus (posterior)
b- the tonsillar fossae
 tri...
stylopharyngeus muscle carries
glossopharyngeal nerve b/w
the superior & middle const.m
(the nerve is at risk during
tonsi...
Blood supply of the tonsils
 Tonsile branches of
1- Lesser Palatine (maxillary
artery)
2- Ascending Palatine ( facial
art...
Hypopharynx
 extends from the upper border of
the epiglottis to the lower border of
the cricoid cartilage where it
contin...
Piriform recess
 inferior to the lateral
glossoepiglottic folds on
either side of the larynx
food and liquid are
diverted...
Muscles of the pharynx
 3 pairs overlapping
constrictors
 3 pairs diagonal muscles
 constrict the pharyngeal
lumen to p...
Cricopharyngeal muscle
 functions as a sphincter
 at the superior end of the
esophagus
( i.e. b/w pharynx and
esophagus)...
Longitudinally arranged muscle
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palatopharyngeus m
salpingopharyngeus
stylopharyngeus m



Arise at base of skull a...
PHARYNGEAL TISSUE SPACES
 Sub-divided into peripharyngeal and intrapharyngeal
space
 Peripharyngeal divides into anterio...
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Nerve supply of pharynx
pharyngeal plexus
 Provided most of the innervation to the pharynx
 Lies in the buccopharyngeal ...
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Blood supply of the pharynx
derived chiefly from
 the Ascending pharyngeal artery
 small branch. Of ECA near its origin ...
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FUNCTIONS O THE PHARYNX
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Respiration
Deglutition.
Phonation.
Protective function

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deglutition
 Deglutition = Swallowing
 Deglutition is the complex
process that moves bolus
of food from mouth
through ph...
Organs of deglutition and related
structures
 During deglutition, the muscles of
mouth, pharynx, larynx and
esophagus coo...

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Esophagus
Stomach
The airway is protected by correct movement of larynx, so
that food and liquid does not enter the...
Stages of deglutition
 • Deglutiton is a
continuous process from
oral cavity to stomach,
divide into 3 stages
 1.oral ph...
Oral phase
 First stage of deglutition
 • The first stage is
voluntary and initiate
deglutition process
 – A mass of ch...
Second stage of deglutition
 Second stage of
deglutition
 The second stage is
involuntary and rapid
 The entire process...
 The bolus is propelled by
pumping action of tongue
base and constriction of
pharyngeal muscles
 Anterior faucial arch
...
Pharyngeal phase
 Pharyngeal phase
 Soft palate is elevated,
sealing off the
nasopharynx from
oropharynx, prevent reflux...
 Elevation and closure of
larynx, to prevent food
from entering airway
 Upper esophageal
sphincter (cricopharyngeus
musc...
Pharyngeal phase
 Larynx is closed off to the bolus
by several mechanisms:
 Larynx is pulled upward and
anteriorly by mu...
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Third stage of deglutition
 The third stage is also
involuntary
 8-20 seconds transmit time
 Start from the point where...
Deglutition

Oral phase (a)
Pharyngeal phase (b)
Esophageal phase (c),(d),(e)
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Deglutition reflex

 Deglutition reflex
 Deglutition reflex is mainly
a protective reflex
 Two main things take
place d...
Deglutition reflex
 Sensory impulses
transmitted as a result of
stimulation of deglutition
receptors on the fauces
 Tons...
Deglutition reflex
 Sensory impulses reach
the deglutition center in
brain stem
 Motor function is mediated
through the ...
EXAMINATION OF THE PHARYNX
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Examination of the nasopharynx:
Post-nasal mirror (posterior rhinoscop...
INVESTIGATIONS OF THE
PHARYNYX
 Plain X-ray
 Barium swallow
 CT scan and MRI
 Angiography
 Contrast fluoroscopy
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APPLIED ASPECT
1. TONSILLITIS:
Generally due to streptococcal
infection.
Generally treated conservativily
with antibiotics...
3. ADENOIDITIS:
infection and inflammation
of the pharyngeal tonsils or
adenoids –
-block
the
orifice of the auditory tube...
Larynx

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Development
 Internal lining from endoderm ,as well as the laryngeal
epithelium and glands
 Muscles and cartilage from 4...
Laryngeal skeleton
 Is a cartilaginous
framework that is firmly
anchored to the hyoid
bone
 Moves up or down with
moveme...
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Thyroid cartilage
 Is the largest of the
laryngeal cartilage
 Paired Lamina
meet in the midline
anteriorly at laryngeal
...
On their outer surface have an oblique line

 for attachment of
1. inferior pharyngeal
constrictor
2. Sternothyroid
3. th...
Cricoid cartilage

 Is an unpaired hyaline
cartilage
 Is ring shaped having a
narrow anterior arch and a
wide posterior ...
Epiglottic cartilage
 Is a leaf-shaped
cartilaginous plate
 Lies posterior to the root of
the tongue
 Anterior surface ...
Arytenoids cartilage
Is pyramid shaped&paired
Sits on the superior surface
of the cricoid lamina
Has an apex Supports the
...
Corniculate cartilage
Is a paired elastic cartilage
that rests on the apex
of the arytenoid cartilage
Lies within the arye...
Ligaments and membranes of the
larynx
Thyrohyoid membrane
 Is a tough, fibrous
membrane that connects
the upper border of...
Cricothyroid membrane
 Inferiorly to the arch of the
cricoid cartilage
 Superiorly to the deep
surface of the thyroid
ca...
Vocal ligament
 Extends between the deep
surface of the thyroid
cartilage and the vocal
process of the arytenoid
cartilag...
Quadrangular membrane
 It forms the lateral wall of
vestibule with free margins
forming aryepiglottic and
vestibular fold...
Laryngeal cavity and folds
 three distinct parts
 is divided by the
vestibular folds and
ventricular folds
– the vestibu...
Vestibule


Lies between the
laryngeal aditus and the
vestibular folds

 Aditus
Is the entrance from
the pharynx into th...
Vestibular fold-false vocal folds
 Paired transverse fold
lying on the side of the
larynx
 Extends from the thyroid
cart...
Ventricle
 Is a boat-shaped
depression
 Extending laterally
between the vestibular fold
and the vocal fold
 Contain gla...
Vocal folds
 Lies inferior to the vestibular
fold and extends between
the thyroid cartilage and the
vocal process of the
...
 Functions to
– Control the flow of air through the rima glottidis
– Produce the sounds of speech

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Rima glottidis

 Interval
between
the
paired vocal folds
 Narrowest part of the
laryngeal cavity
 Opens and closes to
r...
Glottis

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Infraglottic cavity
 Lies between the vocal
fold and the lower border
of the cricoid cartilage
 Is continuous inferiorly...
Vocal folds
during a vibratory cycle
Open for
breathing

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Extrinsic Muscles of the Larynx
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Elevators
Stylohyoid
Mylohyoid
Geniohyoid
Genioglossus
Hyoglossus...
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Extrinsic Muscles elevate and depress the larynx
 Lift larynx during swallowing
 Minimal vertical excursion during norma...
Intrinsic Muscles of the Larynx
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Adductors
Lateral cricoarytenoid
Transverse arytenoid
Oblique arytenoid
Abductor
...
Posterior Cricoarytenoid
 Only abductor muscle
 Origin posterior surface of
cricoid
 Angles up to insert in
muscular pr...
Lateral Cricoarytenoids
 Adductors
 Functions as direct agonist
to posterior cricoarytenoid
 Origin in upper border of
...
Transverse Arytenoids
 Adductors
and
fold
compressors
 Only unpaired intrinsic
muscle of larynx
 Origin in lateral marg...
Oblique Arytenoids
 Adductors
 Origin
in
muscular
process of one arytenoid;
inserts on apex of the
other
 Fibers contin...
Thyroarytenoid Muscles
 Tensors
 Form bulk of muscular
portion of folds
 Origin from inner surface
of thyroid; insert i...
Cricothyroid Muscles
 Tensors
 Origin in anterior-lateral arch of
cricoid; insert a) near lower horn
of thyroid & b) low...
Actions of Intrinsic muscles
 Cricothyroid tenses and
lengthens the vocal lig.
 Posterior cricoarytenoid 
abduct (OPEN...
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Innervation of the larynx
 Superior laryngeal nerve
 Recurrent laryngeal nerve

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Innervation of larynx (makes surgery
at neck risky
– Recurrent laryngeal nerves of
Vagus
– These branch off the Vagus
and ...
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Functions of larynx
 Biological roles of larynx
– prevents foreign
bodies from entering
airway
– fixates thorax by
stoppi...
Examination of larynx
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INDIRECT LARYNGOSCOPY
FLEXIBLE AND RIGID ENDOSCOPES
STROBOSCOPIC EXAMINATION
DIRECT LARYNGO...
INDIRECT LARYNGOSCOPY

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FLEXIBLE ENDOSCOPY

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RIGID ENDOSCOPES

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STROBOSCOPIC EXAMINATION

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DIRECT LARYNGOSCOPE

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CLINICAL ASPECT

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CLINICAL CONSIDERATIONS IN
ORTHODONTIA

Cephalometrics – pharyngeal
relationships

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variables
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AA-PNS
Ap-Ptm
apw2-ppw2-pharyngeal depth
apw4-ppw4-pharyngeal depth
Ba-PNS-dimension of...
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Ptm-SWP-height of nasopharynx
Ptm-s-Ba-shape of the bony nasopharyngeal space
T1-soft tissue shadow
T2

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Mcnamara analysis


Upper pharyngeal space

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

Lower pharyngeal space

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References
 Gray’s Anatomy, 38th edition
 A. K. Datta – Essentials of human anatomy, head and
neck.
 Dhingra – Diseases...
 Anatomical basis of dentistry by liebgott 2nd edition
 Snell clinical anatomy for medical students.

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  • 3 NAMES VENT F / VOCAL F. / TRUE V CORD NINA PRODUCES SOUND OF SPEECH
  • Anatomy of pharynx /certified fixed orthodontic courses by Indian dental academy

    1. 1. ANATOMY OF PHARYNX AND LARYNX AND APPLIED ASPECTS OF PHARYNX AND LARYNX INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com www.indiandentalacademy.com
    2. 2. contents Pharynx  Anatomy  Development  Divisions  Muscles  Pharyngel tissue spaces  Innervation  Arterial supply  Venous supply  Lymphatic drinage  Functions  Applied aspects  Examination of the pharynx www.indiandentalacademy.com
    3. 3. Larynx  development  Anatomy Cartilage Ligaments Fibrous membreane  Joints Muscles        Laryngeal cavity Para lumenal spaces Vascular supply Lymphatic drinage Innervation Clinical aspects www.indiandentalacademy.com Functions
    4. 4.  Cephalometrics related to pharnyx  References www.indiandentalacademy.com
    5. 5. Pharynx www.indiandentalacademy.com
    6. 6. Fibro muscular tube Attached to the base of the skull Continuous with the esophagus inferiorly www.indiandentalacademy.com
    7. 7. Structures of the pharynx  Has a wall consists of 4 layers 1-mucosa 2-pharyngobasilar fascia no submucosa,so even slight edema will result in a painful ‘’ sore throat’’ 3-muscular coat -externally pharngeal costrictor muscle -internally longitudinal muscle 4- buccopharyngeal fascia  Contains pharyngeal plexus www.indiandentalacademy.com
    8. 8. Development www.indiandentalacademy.com
    9. 9. Pharyng eal Arch Cranial Nerve Muscle derivativ e Skeletal Derivativ e 1 Mandib ular Trigemin al nerve Muscle of masticatio n Tensor tympani Incus, ant. Lig of malleus Facial nerve Muscles of facial expressio n Stapes, Hyoid bone 2 Hyoid 3 Glossoph stylophary Horns of aryngeal ngeas hyoid nerve 4 Vagus nerve Striated muscles of oesophag us 5 None none 6 Merges with 4 none www.indiandentalacademy.com 9
    10. 10. Pharyn geal Pouch Derivative 1 Epithelium of tympanic cavity and auditory tube 2 Epithelium of tonsil 3 Inferior parathyroid glands and epithelium of thymus 4 Superior parathyroid glands. www.indiandentalacademy.com 10
    11. 11. Pharyngeal (grooves): Clefts located arches between these are spaces, thus contain no germ layer components initially 4 clefts of which only one develops as 2nd arch grows over all other clefts filling them in 1st cleft forms the External Auditory Meatus www.indiandentalacademy.com 11
    12. 12. Divisions    nasopharynx oropharynx hypopharynx www.indiandentalacademy.com
    13. 13. Nasopharynx -extends from the base of the skull to the soft palate -functionally a part of the respiratory system -remains open at all times Anterior nasal choanaenasal cavity Posterior and superior body of the sphenoid ,basilar occipital bone and the arch of the atlas Floor-soft palate Inferiorly-communicates with the oropharynx at the pharyngeal isthmus. www.indiandentalacademy.com
    14. 14. Pharyngeal tonsils -includes a-pharyngeal tonsils b-auditory tube embedded in the mucosa of the posterior wall of the Nasopharynx. may impair breathing when enlarged and are then called adenoid. www.indiandentalacademy.com
    15. 15. www.indiandentalacademy.com
    16. 16. Oropharynx  extends from the soft palate above  to the upper border of epiglottis below  at the level of the bodies of the C2 and C3 vertebrae  anterior  the base of the tongue  inferior  the epiglottis (uppersurface of the larynx) a-median glossoepiglottic fold b- lateral glossoepiglottic folds c- the vallecular recess(3rd branchial pouch)  contains palatine tonsils a- the faucial pillars (arch or fold) b- the tonsillar fossae (2nd www.indiandentalacademy.com branchial pouch)
    17. 17. a- the faucial pillars (arch or fold)  palatoglosus (anterior), palatopharyngus (posterior) b- the tonsillar fossae  triangular-shaped  muscular bed formed by superior pharyngeal constrictor muscle  contains a mass of lymphoid tissue (palatine tonsil)  lie b/w the diverging fauces on each sides in space b/w the superior and middle pharyngeal constrictor muscle posteriorly middle pharyngeal constrictor Muscle and stylohyoid ligament anteriorlyhyoglossus muscle www.indiandentalacademy.com
    18. 18. stylopharyngeus muscle carries glossopharyngeal nerve b/w the superior & middle const.m (the nerve is at risk during tonsillectomy)  extends from the base of the tongue to the edge of the soft palate  medial surface intratonsilar cleft + 12-15 tonsillar crypts  lateral surface fibrous tonsillar capsule derived from the pharyngobasilar fascia  easly separated from the pharyngeal wall  except at the root of the tongue (tonsillar arteries enterance) www.indiandentalacademy.com
    19. 19. Blood supply of the tonsils  Tonsile branches of 1- Lesser Palatine (maxillary artery) 2- Ascending Palatine ( facial artery) 3- Lingual artery (ECA) 4- Ascending Pharyngeal artery (ECA) 5- Facial artery (main source) (ECA)  Venous drainage of tonsil peritonsillar venous plexus tonsillar branch of the lingual vein (main vein)source of a profuse venous hemorrhage after www.indiandentalacademy.com tonsillectomy
    20. 20. Hypopharynx  extends from the upper border of the epiglottis to the lower border of the cricoid cartilage where it continuous with the esophagus at the level C4,5,and 6 vertebrae  It has anterior wall,posterior wall and lateral walls  In lateral wall there is a depression called piriform fossa www.indiandentalacademy.com
    21. 21. Piriform recess  inferior to the lateral glossoepiglottic folds on either side of the larynx food and liquid are diverted to either side of the larynx into these recesses upon deglutition  swallowed foreign bodies may lodge in these recesses  internal laryngeal nerve can be anesthetized where it lies deep to the mucosa of the piriform recess www.indiandentalacademy.com
    22. 22. Muscles of the pharynx  3 pairs overlapping constrictors  3 pairs diagonal muscles  constrict the pharyngeal lumen to propel food and drink when swallowing 1-Superior constrictor 2-Middle constrictor 3-Inferior consrictor  lamina of thyroid cartilage and cricoid pharyngeal raphe www.indiandentalacademy.com
    23. 23. Cricopharyngeal muscle  functions as a sphincter  at the superior end of the esophagus ( i.e. b/w pharynx and esophagus)  faliure of the cricopharyngeaus to relax during swallowing occasionally causes the mucosa to herniate through the inferior constrictor , forming a pharyngeal diverticulum www.indiandentalacademy.com
    24. 24. Longitudinally arranged muscle    palatopharyngeus m salpingopharyngeus stylopharyngeus m  Arise at base of skull and descend b/w pharyngeal constrictor and pharyngobasilar fascia to insert into fascia and thyroid cartilage www.indiandentalacademy.com
    25. 25. PHARYNGEAL TISSUE SPACES  Sub-divided into peripharyngeal and intrapharyngeal space  Peripharyngeal divides into anterior,posteriorly,and laterally  Anterior-it is formed by submandibular and submental space.  Posterirly by the retropharyngeal space.  Laterally by para pharyngeal space.  Peritonsillar space is an important part of the intra pharyngeal space www.indiandentalacademy.com
    26. 26. www.indiandentalacademy.com
    27. 27. Nerve supply of pharynx pharyngeal plexus  Provided most of the innervation to the pharynx  Lies in the buccopharyngeal fascia  covering the outer surface of the pharyngeal constrictor muscle  Supplies the 1-muscles of the pharynx except the stylopharyngeus 2-muscles of the palate except the tensor veli palatini 3-mucosa of the pharynx and cartilagenous portion of the auditory tube except part of the roof (phary.br. of V2) www.indiandentalacademy.com
    28. 28. www.indiandentalacademy.com
    29. 29. Blood supply of the pharynx derived chiefly from  the Ascending pharyngeal artery  small branch. Of ECA near its origin ascends b/w pharynx and the ICA Also is supplied regionally by the  1- ascending palatine artery from the facial artery  2- superior thyroid artery  3- inferior thyroid artery www.indiandentalacademy.com
    30. 30. www.indiandentalacademy.com
    31. 31. www.indiandentalacademy.com
    32. 32. www.indiandentalacademy.com
    33. 33. FUNCTIONS O THE PHARYNX     Respiration Deglutition. Phonation. Protective function www.indiandentalacademy.com
    34. 34. deglutition  Deglutition = Swallowing  Deglutition is the complex process that moves bolus of food from mouth through pharynx into esophagus and then to stomach www.indiandentalacademy.com
    35. 35. Organs of deglutition and related structures  During deglutition, the muscles of mouth, pharynx, larynx and esophagus coordinate properly in a complex process; to move food and liquid into stomach  Organs of deglutition  Oral cavity  Pharynx -Nasopharynx -Oropharynx -Laryngopharynx www.indiandentalacademy.com
    36. 36.    Esophagus Stomach The airway is protected by correct movement of larynx, so that food and liquid does not enter the airway www.indiandentalacademy.com
    37. 37. Stages of deglutition  • Deglutiton is a continuous process from oral cavity to stomach, divide into 3 stages  1.oral phase  2.pharyngeal phase  3.esophageal phase www.indiandentalacademy.com
    38. 38. Oral phase  First stage of deglutition  • The first stage is voluntary and initiate deglutition process  – A mass of chewed, moistened food, a bolus, is moved to the back of the oral cavity by the tongue  – The lip and buccal muscles help keep bolus from dispersing either anteriorly out of oral cavity or laterally into oral www.indiandentalacademy.com vestibule
    39. 39. Second stage of deglutition  Second stage of deglutition  The second stage is involuntary and rapid  The entire process occurs in less than 2 seconds  Start from the point at where the deglutition reflex is triggered at the anterior faucial arch through the upper esophageal sphincter into the www.indiandentalacademy.com esophagus
    40. 40.  The bolus is propelled by pumping action of tongue base and constriction of pharyngeal muscles  Anterior faucial arch  Soft palate  Palatoglossal arch  Base of tongue www.indiandentalacademy.com
    41. 41. Pharyngeal phase  Pharyngeal phase  Soft palate is elevated, sealing off the nasopharynx from oropharynx, prevent reflux of food into nasal cavity  Initiation of pharyngeal peristalsis to pick up and carry the bolus www.indiandentalacademy.com
    42. 42.  Elevation and closure of larynx, to prevent food from entering airway  Upper esophageal sphincter (cricopharyngeus muscle) relaxation www.indiandentalacademy.com
    43. 43. Pharyngeal phase  Larynx is closed off to the bolus by several mechanisms:  Larynx is pulled upward and anteriorly by muscles of neck, cause epiglottis to swing backward over the opening of larynx.  Closure of larynx at all 3 sphincters Epiglottis / aryepiglottic folds  False vocal folds  True vocal folds  Cessation of respiration www.indiandentalacademy.com
    44. 44. www.indiandentalacademy.com
    45. 45. Third stage of deglutition  The third stage is also involuntary  8-20 seconds transmit time  Start from the point where the bolus enters the esophagus at the upper esophageal sphincter  Until the bolus passes into stomach at the lower esophageal sphincter  During third stage, combination of gravity and peristalsis, push the bolus from esophagus down to www.indiandentalacademy.com
    46. 46. Deglutition Oral phase (a) Pharyngeal phase (b) Esophageal phase (c),(d),(e) www.indiandentalacademy.com
    47. 47. Deglutition reflex  Deglutition reflex  Deglutition reflex is mainly a protective reflex  Two main things take place during reflex  A squeezing action squeezes the bolus with muscles that pull food down to the stomach. This action is called peristalsis.  Larynx closes off to keep food out of the airway. The epiglottis folds down and the vocal folds shut. www.indiandentalacademy.com
    48. 48. Deglutition reflex  Sensory impulses transmitted as a result of stimulation of deglutition receptors on the fauces  Tonsils  Soft palate  Base of tongue  Posterior pharyngeal wall  By the 7th, 9th and 10th cranial nerves www.indiandentalacademy.com
    49. 49. Deglutition reflex  Sensory impulses reach the deglutition center in brain stem  Motor function is mediated through the 5th, 9th, 10th and 12th cranial nerves  To initiate muscle contraction  Elevation of soft palate  Elevation and closure of larynx  Peristalsis of pharynx and esophagus. www.indiandentalacademy.com
    50. 50. EXAMINATION OF THE PHARYNX             Examination of the nasopharynx: Post-nasal mirror (posterior rhinoscopy). Flexible fiberoptic endoscopy (under local anesthesia). Rigid endoscope introduced through the nose or mouth (under L.A. or G.A.) using different angles (0°, 30°, 70°, or 90°. Examination of the oropharynx: Examination is done through an open mouth with tongue depressor. Digital palpation whenever malignancy is suspected. Examination of the laryngopharynx (hypopharynx): By indirect laryngoscopy (using laryngeal mirror) By flexible nasolaryngoscope. By rigid endoscope (90° or 120°). By direct laryngoscopy under general anaesthesia. www.indiandentalacademy.com
    51. 51. INVESTIGATIONS OF THE PHARYNYX  Plain X-ray  Barium swallow  CT scan and MRI  Angiography  Contrast fluoroscopy www.indiandentalacademy.com
    52. 52. APPLIED ASPECT 1. TONSILLITIS: Generally due to streptococcal infection. Generally treated conservativily with antibiotics. Chronic or recurrent cases may require surgical removal or tonsillectomy 2. TONSILLECTOMY: Most common postoperative complication- hemorrhage www.indiandentalacademy.com
    53. 53. 3. ADENOIDITIS: infection and inflammation of the pharyngeal tonsils or adenoids – -block the orifice of the auditory tube pain and temporary deafness 4. PHARYNGEAL DYSPHAGIA 5. VAGAL REFLEXES www.indiandentalacademy.com
    54. 54. Larynx www.indiandentalacademy.com
    55. 55. Development  Internal lining from endoderm ,as well as the laryngeal epithelium and glands  Muscles and cartilage from 4th&6th pharyngeal arch  At week4,on the ventral side of the primitive gut,a pocket forms that bulges out from the gut-laryngo tracheal diverticulum  Ant(ventrally)=laryngeal tracheal tube  Post(dorsally=eosphageal tube  Opening of laryngeal diverticulum=orifice  Epiglottis and cuneiform cartilages are derived from 4th arch.  Cricoid,arytenoid,corniculate are developed from 6th www.indiandentalacademy.com th th
    56. 56. Laryngeal skeleton  Is a cartilaginous framework that is firmly anchored to the hyoid bone  Moves up or down with movement of the hyoid bone Consists of the paired – arytenoid, – corniculate – cuneiform cartilage the unpaired – thyroid – cricoid www.indiandentalacademy.com – epiglottic cartilages
    57. 57. www.indiandentalacademy.com
    58. 58. Thyroid cartilage  Is the largest of the laryngeal cartilage  Paired Lamina meet in the midline anteriorly at laryngeal prominence, but diverge posteriorly www.indiandentalacademy.com
    59. 59. On their outer surface have an oblique line  for attachment of 1. inferior pharyngeal constrictor 2. Sternothyroid 3. thyrohyoid muscles www.indiandentalacademy.com
    60. 60. Cricoid cartilage  Is an unpaired hyaline cartilage  Is ring shaped having a narrow anterior arch and a wide posterior lamina  Lies at the level of the sixth cervical vertebra Is connected Superiorly  to the thyroid cartilage by way of the cricothyroid joint and the cricothyroid membrane Inferiorly  to the first tracheal ring by way www.indiandentalacademy.com of the cricotracheal ligament
    61. 61. Epiglottic cartilage  Is a leaf-shaped cartilaginous plate  Lies posterior to the root of the tongue  Anterior surface is connected to the tongue by median glossoepiglottic fold.  Posterior surface is covered with mucous membrane. www.indiandentalacademy.com
    62. 62. Arytenoids cartilage Is pyramid shaped&paired Sits on the superior surface of the cricoid lamina Has an apex Supports the corniculate cartilage within the aryepiglottic fold Has a base Forms a synovial joint with the lamina of the cricoid cartilage Has a muscular process Provides attachment for the lateral cricoarytenoid, posterior cricoarytenoid, and thyroarytenoid muscles Has a vocal process Provides attachment for the vocal ligament and vocalis www.indiandentalacademy.com muscle
    63. 63. Corniculate cartilage Is a paired elastic cartilage that rests on the apex of the arytenoid cartilage Lies within the aryepiglottic fold of mucous membrane Cuneiform cartilage Is a paired elastic cartilage that lies in the aryepiglottic fold superior to the corniculate cartilage www.indiandentalacademy.com
    64. 64. Ligaments and membranes of the larynx Thyrohyoid membrane  Is a tough, fibrous membrane that connects the upper border of the thyroid cartilage to the lower border of the hyoid bone  Its lateral portion is pierced by the internal laryngeal nerve and superior laryngeal artery www.indiandentalacademy.com
    65. 65. Cricothyroid membrane  Inferiorly to the arch of the cricoid cartilage  Superiorly to the deep surface of the thyroid cartilage and to the vocal process of the arytenoid Cartilage  Is thickened Along its free upper border to form the vocal ligament  In the midline to form the median cricothyroid ligament  Extend upward deep to thyroid cartilage as conus elasticus www.indiandentalacademy.com
    66. 66. Vocal ligament  Extends between the deep surface of the thyroid cartilage and the vocal process of the arytenoid cartilage  Is the thickened free border of the conus elasticus portion of the cricothyroid membrane www.indiandentalacademy.com
    67. 67. Quadrangular membrane  It forms the lateral wall of vestibule with free margins forming aryepiglottic and vestibular fold  Connects the arytenoid cartilage and the epiglottic cartilage  Lies in the lateral wall of the vestibule separating it from the piriform recess Vestibular ligament – Is the free lower border of the quadrangular Membrane – Lies in the vestibular fold www.indiandentalacademy.com
    68. 68. Laryngeal cavity and folds  three distinct parts  is divided by the vestibular folds and ventricular folds – the vestibule – the ventricle – the infraglottic cavity, www.indiandentalacademy.com
    69. 69. Vestibule  Lies between the laryngeal aditus and the vestibular folds  Aditus Is the entrance from the pharynx into the larynx  Rima vestibuli space between the paired vestibular folds www.indiandentalacademy.com
    70. 70. Vestibular fold-false vocal folds  Paired transverse fold lying on the side of the larynx  Extends from the thyroid cartilage to the arytenoid cartilage above the vocal fold  Contains  Vestibular ligament  Upper fibers of the thyroarytenoid muscle  Closes to protect the airway during swallowing and during forced expiration against a closed airway www.indiandentalacademy.com
    71. 71. Ventricle  Is a boat-shaped depression  Extending laterally between the vestibular fold and the vocal fold  Contain glands that lubricate vocal fold ( as vocal folds by themselves lack mucous glands )  May extend superiorly in anterior part as saccule of variable size www.indiandentalacademy.com
    72. 72. Vocal folds  Lies inferior to the vestibular fold and extends between the thyroid cartilage and the vocal process of the arytenoid cartilage  Contains the – Vocal ligament (no submucosa-excluding edema) – Vocalis portion of the thyroarytenoid muscle www.indiandentalacademy.com
    73. 73.  Functions to – Control the flow of air through the rima glottidis – Produce the sounds of speech www.indiandentalacademy.com
    74. 74. Rima glottidis  Interval between the paired vocal folds  Narrowest part of the laryngeal cavity  Opens and closes to regulate the passage of air • Obstruction of the laryngeal airway at the rima glottidis may result from aspirated food such as a piece of meat www.indiandentalacademy.com
    75. 75. Glottis www.indiandentalacademy.com
    76. 76. Infraglottic cavity  Lies between the vocal fold and the lower border of the cricoid cartilage  Is continuous inferiorly with the trachea  Is related anteriorly to the cricothyroid membrane  An emergency airway made through the cricothyroid membrane will enter the airway below the vocal folds where obstruction of the airway most commonly www.indiandentalacademy.com occurs.
    77. 77. Vocal folds during a vibratory cycle Open for breathing www.indiandentalacademy.com
    78. 78. Extrinsic Muscles of the Larynx             Elevators Stylohyoid Mylohyoid Geniohyoid Genioglossus Hyoglossus Inferior laryngeal constrictor Digastric Depressors Sternothyroid Sternohyoid Omohyoid Thyrohyoid Other Cricopharyngeus www.indiandentalacademy.com
    79. 79. www.indiandentalacademy.com
    80. 80. www.indiandentalacademy.com
    81. 81. Extrinsic Muscles elevate and depress the larynx  Lift larynx during swallowing  Minimal vertical excursion during normal speech www.indiandentalacademy.com
    82. 82. Intrinsic Muscles of the Larynx     Adductors Lateral cricoarytenoid Transverse arytenoid Oblique arytenoid Abductor Posterior cricoarytenoid Tensors  Medial thyroarytenoid  Cricothyroid Relaxers  Lateral thyroarytenoid www.indiandentalacademy.com
    83. 83. Posterior Cricoarytenoid  Only abductor muscle  Origin posterior surface of cricoid  Angles up to insert in muscular process of arytenoid on same side  Rotates vocal process laterally  Innervated by recurrent laryngeal nerve www.indiandentalacademy.com
    84. 84. Lateral Cricoarytenoids  Adductors  Functions as direct agonist to posterior cricoarytenoid  Origin in upper border of cricoid arch and inserts onto muscular process of arytenoid on same side  Rotates muscle process forward and causes vocal process to ‘toe in’ at midline www.indiandentalacademy.com
    85. 85. Transverse Arytenoids  Adductors and fold compressors  Only unpaired intrinsic muscle of larynx  Origin in lateral margin of one arytenoid and traverses the distance to the same spot on the other  Approximate bodies of arytenoids together  Innervated by recurrent laryngeal nerve www.indiandentalacademy.com
    86. 86. Oblique Arytenoids  Adductors  Origin in muscular process of one arytenoid; inserts on apex of the other  Fibers continue to lateral border of epiglottis --> aryepiglottic folds  Active during swallow & bring vocal cords closer together by approximating apex www.indiandentalacademy.com
    87. 87. Thyroarytenoid Muscles  Tensors  Form bulk of muscular portion of folds  Origin from inner surface of thyroid; insert in vocal process and lateral surface of arytenoids  Shorten to lower pitch; also adduct glottis by muscular tension and elasticity www.indiandentalacademy.com
    88. 88. Cricothyroid Muscles  Tensors  Origin in anterior-lateral arch of cricoid; insert a) near lower horn of thyroid & b) lower margin of lateral thyroid wall  Innervated by external branch of superior laryngeal nerve ( only intrinsic muscle not innervated by recurrent laryngeal nerve )  Increases distance between thyroid and arytenoid cartilages, increasing pitch by stretching folds  Tense folds by lengthening them www.indiandentalacademy.com
    89. 89. Actions of Intrinsic muscles  Cricothyroid tenses and lengthens the vocal lig.  Posterior cricoarytenoid  abduct (OPENS )  Lateral cricoarytenoid  adduct (CLOSE)  Transverse arytenoid adduct (CLOSE)  Oblique arytenoidsadduct (CLOSE)  Thyroarytenoid  decreases the tension & length  Vocalis (portion of the thyroarytenoid lying within the vocal fold) www.indiandentalacademy.com
    90. 90. www.indiandentalacademy.com
    91. 91. Innervation of the larynx  Superior laryngeal nerve  Recurrent laryngeal nerve www.indiandentalacademy.com
    92. 92. Innervation of larynx (makes surgery at neck risky – Recurrent laryngeal nerves of Vagus – These branch off the Vagus and make a big downward loop under vessels, then up to larynx in neck – Left loops under aortic arch – Right loops under right subclavian artery – Damage to one: hoarseness – Damage to both: can only whisper www.indiandentalacademy.com
    93. 93. www.indiandentalacademy.com
    94. 94. www.indiandentalacademy.com
    95. 95. Functions of larynx  Biological roles of larynx – prevents foreign bodies from entering airway – fixates thorax by stopping airflow at glottis level, permitting heavy lifting/weight supporting feats www.indiandentalacademy.com
    96. 96. Examination of larynx     INDIRECT LARYNGOSCOPY FLEXIBLE AND RIGID ENDOSCOPES STROBOSCOPIC EXAMINATION DIRECT LARYNGOSCOPE www.indiandentalacademy.com
    97. 97. INDIRECT LARYNGOSCOPY www.indiandentalacademy.com
    98. 98. FLEXIBLE ENDOSCOPY www.indiandentalacademy.com
    99. 99. RIGID ENDOSCOPES www.indiandentalacademy.com
    100. 100. STROBOSCOPIC EXAMINATION www.indiandentalacademy.com
    101. 101. DIRECT LARYNGOSCOPE www.indiandentalacademy.com
    102. 102. CLINICAL ASPECT www.indiandentalacademy.com
    103. 103. www.indiandentalacademy.com
    104. 104. www.indiandentalacademy.com
    105. 105. www.indiandentalacademy.com
    106. 106. CLINICAL CONSIDERATIONS IN ORTHODONTIA Cephalometrics – pharyngeal relationships www.indiandentalacademy.com
    107. 107. www.indiandentalacademy.com
    108. 108. variables             AA-PNS Ap-Ptm apw2-ppw2-pharyngeal depth apw4-ppw4-pharyngeal depth Ba-PNS-dimension of the bony pharynx Ip-Kp-smallest distance Mp-Lp-smallest distance N-S-Ptm-shape of the bony nasopharyngeal space P1 P2 P3 Ptm-PPW-depth of nasopharynx www.indiandentalacademy.com
    109. 109.     Ptm-SWP-height of nasopharynx Ptm-s-Ba-shape of the bony nasopharyngeal space T1-soft tissue shadow T2 www.indiandentalacademy.com
    110. 110. Mcnamara analysis  Upper pharyngeal space www.indiandentalacademy.com
    111. 111.  Lower pharyngeal space www.indiandentalacademy.com
    112. 112. References  Gray’s Anatomy, 38th edition  A. K. Datta – Essentials of human anatomy, head and neck.  Dhingra – Diseases of ENT 4th edition  B.D. Chaurasia – Human Anatomy, head and neck, 4th edition.  Athanasiou – Orthodontic Cepahlometry  Grant’s Atlas of Anatomy 10th edition  Jacobson – Radiographic Cephalometry 2nd edition.  Agur dalley-Grants atlas of anatomy 12th edition www.indiandentalacademy.com
    113. 113.  Anatomical basis of dentistry by liebgott 2nd edition  Snell clinical anatomy for medical students. www.indiandentalacademy.com
    114. 114. www.indiandentalacademy.com

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