4. INTRODUCTION
Deglutition - Movement of substances from the mouth
to the stomach via the oesophagus
Reflexive and voluntary actions of nerves and muscles
produce this coordinated movement
Co-ordinated activity of muscles of oral cavity,
pharynx and oesophagus
Learned early in development (15 weeks in utero)
Average person swallows from 200 to 2,400 times per
day
4
5. DEFNITION
The coordination of voluntary and involuntary muscle contractions at the
initiation of digestion; the act of swallowing
-GPT 9
5
6. Swallowing is a complicated mechanism, principally because the pharynx subserves
respiration and swallowing
The pharynx is converted to a food tract only for a brief period
Respiration is not compromised because of swallowing
6
Swallowing
Oesophageal(
Involuntary)
Pharyngeal
(Involuntary)
Initiation
(Voluntary)
7. Anatomy Of Deglutition
55 muscles of the oral, pharyngeal and
laryngeal region are involved
5 cranial nerves – V, VII, IX, XII are
involved
2 cervical nerve roots
Brainstem centres
7
8. Components of deglutition
Deglutition has 3 components
Passage of bolus from oral cavity to stomach
Protection of airway
Inhibition of air entry into the stomach
8
11. Theory of constant proportion
Describes passage of bolus through upper git in three phases
Oral phase – bolus is formed and transported under voluntary control to
pharynx
Pharyngeal phase – pharynx is activated to propel bolus to oesophagus
Oesophageal phase –passage of bolus to stomach by oesophageal
contraction
11
12. Theory Of Oral Expulsion
The oral expulsion arising from contraction of tongue and
mylohyoid throws bolus into the stomach
12
13. Theory of negative pressure
The tongue is brought forward to create a negative pressure which is
accentuated by the descent of the larynx and therefore the food is
sucked into the oesophagus
13
14. Theory of Integral Function
Based on myometric and electromyographic studies and considers
the act of swallowing as a total dynamic process
Most accepted theory
14
16. Oral Stage - initiates the swallowing process (Voluntary stage)
Pharyngeal stage - passage of food through the pharynx into the
oesophagus (Involuntary)
Oesophageal stage – transportation of food from the pharynx to the
stomach (Involuntary)
16
17. Oral Stage
When the food is ready for swallowing, it is
“voluntarily” squeezed or rolled posteriorly into
the pharynx by pressure of the tongue upward
and backward against the palate
Elevators of mandible are raised
Buccinator contracts to prevent food from going
into vestibule
It is the only voluntary stage in the deglutition
sequence
17
18. Pharyngeal stage
Bolus of food enters the posterior mouth and pharynx
A series of automatic pharyngeal muscle contractions is seen
The soft palate is pulled upward to prevent reflux of food into the
nasal cavities
Palatopharyngeal folds are pulled medially to approximate each
other – form a slit
18
19. Vocal cords of the larynx are approximated
Larynx is pulled upward and anteriorly by the neck
muscles
Epiglottis swung backward over the opening of the larynx
Upper oesophageal sphincter is relaxed
Muscular wall of the pharynx contracts and relaxes to push
the food downward (propulsive contraction)
Entire process occurs in less than 2 seconds
19
20. Bolus can enter into 4 paths
Back to mouth
Upwards into nasopharynx
Forwards into larynx
Downwards into oesophagus
20
21. Entrance Of Bolus Prevented By
Back into mouth
Position of tongue
High intraoral pressure developed by movement tongue
Upwards into Nasopharynx
Elevation of soft palate along with uvula
21
22. Forwards into larynx
Approximation of vocal cords
Forward and upward movement of larynx
Backward movement of epiglottis to seal larynx
Temporary arrest of breathing
22
23. Effect Of Swallowing On Respiration
The swallowing center specifically inhibits the respiratory center of
the medulla during this time, halting respiration at any point in its
cycle to allow swallowing to proceed
Swallowing occurs during expiratory phase of respiration
23
24. Oesophageal stage
Esophagus exhibits two types of peristaltic
24
Primary peristalsis is
simply continuation of the
peristaltic wave that begins
in the pharynx and spreads
into the oesophagus during
the pharyngeal stage of
swallowing
Secondary peristaltic
waves result from
distention of the
oesophagus
itself by the retained food
25. Secondary waves continue until all the food has emptied into the
stomach
Pharyngeal wall and upper third of the oesophagus have striated
muscles
25
26. Peristaltic waves in these regions are controlled by skeletal nerve
impulses from the glossopharyngeal and vagus nerves
Lower two thirds of the esophagus has smooth muscle, but this
portion of the oesophagus is also strongly controlled by the vagus
nerves that act through connections with the oesophageal myenteric
nervous system
26
27. 27
Muscles Associated With Swallowing
• Muscle of the Tongue
• Muscle of Soft Palate
• Muscle of the Pharynx
29. Intrinsic Muscles
Superior Longitudinal lies beneath the mucous membrane, shortens the
tongue and makes dorsum concave.
Inferior Longitudinal muscle is a narrow band lies close to inferior
surface of tongue, shortens tongue makes dorsum convex
Transverse muscle extends from medium septum to margin, makes the
tongue narrow and elongated.
Vertical Muscle found at the border of the anterior part of tongue, makes
tongue broad and flattened
29
32. Genioglossus
Action
Protrusion of tongue
Depress the dorsum and make it
concave
Action – depression of tongue
32
Hyoglossus
Styloglossus
Action – moves the tongue
upwards and backwards
Action – elevates root,
approximates
palatoglossal arch, closes
oropharyngeal isthmus
Palatoglossus
33. Applied Anatomy
Injury to hypoglossal nerve produces paralysis of the muscles of the
tongue on the side of lesion.
In cases of acute glossitis tongue fills the oral cavity & protrudes
out of it causing difficulty in mastication
Glossectomy patients require rehabilitation for speech and deglutiton
33
34. Mobile flap suspended from the posterior border of the hard palate,
sloping down and back between the oral and nasal parts of the pharynx
Thick fold of mucosa enclosing an aponeurosis, muscular tissue,
vessels, nerves, lymphoid tissue and mucous glands
34
Soft Palate
35. Classification of soft palate
Based on the angle that soft palate makes with the hard palate : By HOUSE
a. CLASS I
b. CLASS II
c. CLASS III
35
37. Anterior surface of soft palate is concave and has a median raphe.
Posterior surface convex and continuous with the nasal floor.
Uvula projects downward from its posterior border
37
41. 12 to 14 cm long Musculo-membranous tube shaped like an inverted cone
Extends from cranial base to lower border of cricoid cartilage where it
becomes continuous with oesophagus
There are three circular constrictor and three longitudinal elevators
41
43. Superior Constrictor
Quadrilateral sheet of muscle
Thinner than the other two constrictors
Attaches to
Pterygoid hamulus
Posterior border of the pterygomandibular raphe
Posterior end of the mylohyoid line of the mandible
Side of the tongue
43
44. Middle constrictor
Fan-shaped sheet
Attached to
lesser cornu of the hyoid
upper border of the greater cornu of the hyoid
lower part of the stylohyoid ligament
44
45. Inferior Constrictor
thickest of the three constrictor muscles
Divided in two parts
thyropharyngeus
cricopharyngeus
Thyropharyngeus arises from- oblique line of the thyroid lamina, by a
small slip from the inferior cornu & some additional fibers arise from
a tendinous cord that loops over cricothyroid
45
46. Cricopharyngeus arises from the side of the cricoid cartilage
between the attachment of cricothyroid and the articular facet for the
inferior thyroid cornu
Cricopharyngeus consists of a superficial upper oblique portion – the
pars oblique – and a lower, deeper, transverse portion – the pars
fundiformis
46
47. Insertion of Constrictor of Pharynx
Inserted into median raphe on posterior of pharynx.
Upper end of raphe reaches base of the skull where it is attached to
pharyngeal tubercle on basilar part of occipital bone
47
51. Dysphagia
Lack of coordination or strength of muscles or mechanical obstruction
If contractions fail to develop progress, bolus distends the oesophageal
lumen and causes discomfort
Mechanical narrowing of oesophageal lumen obstructs passage of
bolus despite adequate contractions
Abnormal sensory perception in oesophagus may cause sensation of
dysphagia even after bolus is cleared.
51
52. Vomiting
Is highly integrated and complex reflex involving both autonomic
and somatic neural pathways
Synchronous contraction of diaphragm , intercostal muscles and
abdominal muscles raises intra abdominal pressure combined
with forcible ejection of gastric contents.
52
53. Deglutition Apnoea
Arrest of breathing during deglutition.
Occurs reflex during pharyngeal stage.
When bolus is pushed into oesophagus from pharynx during
pharyngeal stage, there is possibility for the bolus to enter the
respiratory passage through trachea which may cause choking.
53
54. Aspiration
Defined as the inhalation of oropharyngeal or gastric contents
into the larynx & lower respiratory tract.
Aspiration Pneumonitis (Mendelson’s Syndrome) chemical
injury caused by the inhalation of sterile gastric contents.
Aspiration Pneumonia is an infectious process caused by the
inhalation of oropharyngeal secretions that are colonized by
pathogenic bacteria.
54
55. Risk Factors For Oropharyngeal Aspiration
Elderly, neurologic dysphagia, GERD
Poor oral hygiene-colonization by respiratory tract
pathogens
Silent aspiration is common in stroke.
Management
Upper respiratory suction, Antibiotics, ET intubation for
airway
55
56. Cricopharyngeal Dysfunction
Failure of the tonically contracted upper oesophageal sphincter to
relax and open when one swallows
Symptoms - pills or solid food begin to lodge at the level of the
lower part of the larynx.
Treatment - Resolved through surgical procedure - Cricopharyngeal
Myotomy
56
57. Choking
Mechanical obstruction of the flow of air from the
environment into the lungs that prevents breathing.
Causes - Foreign body, respiratory disease, compression of
laryngopharynx
57
58. Signs & symptoms
Person cannot speak or cry, violent cough, difficult in breathing
produce wheezing sounds, clutches throat, if respiration not
restored ,then cyanosis
Treatment
BLS
Heimlich maneuver
58
60. Presbyphagia
Characteristic changes in the swallowing mechanism of otherwise
healthy older adults.
AGE ASSOCIATED CHANGES
Demonstrate delay in onset of specific pharyngeal events
Swallowing is slow
Larger duration
Upper Oesophageal Sphincter opening is delayed
Chance of Aspiration-more
60
61. Odynophagia - Painful swallowing
Globus Hystericus - Sensation of lump lodged in throat
Phagophobia - Fear of swallowing as in rabies, tetanus, pharyngeal
paralysis due to fear of aspiration.
61
62. Gag Reflex
Stimulation of sensitive areas of pharynx, soft palate, uvula, tongue
62
Stimulation of Trigeminal & Glossopharyngeal & Vagus nerves
Uncoordinated & spasmodic movements of
swallowing muscles
Gagging
63. Gag reflex – a normal defence mechanism that prevents foreign
bodies from entering trachea , pharynx , larynx.
5 trigger zones for gagging –
Palatoglossal fold & Palatopharyngeal fold
Palate
Base of Tongue
Uvula
Posterior pharyngeal wall
63
64. Treatment - Removal of factors
Local anaesthetic may be used while working
Drugs like atropine along with a sedative may be prescribed
Acupressure
64
66. Classification of soft palate
Based on the angle that soft palate makes with the hard palate : By HOUSE
a. CLASS I
b. CLASS II
c. CLASS III
66
67. Defects of soft palate
Congenital
• Embryonic development
interrupted
Acquired
• Surgical resection of
neoplastic disease
Developmental
• Diminished capacity of soft
palate to respond to
functional demands
• Muscular or neurologic
diseases.
67
68. Palatopharyngeal insufficiency
• Some or all anatomic structures are absent
Palatopharyngeal incompetence
• Lacks movement because of disease or trauma affecting muscular or
neurologic capacity
Palatopharyngeal inadequacy
• Incompetence or insufficiency & also reduction or absence of pharyngeal
wall function
68
69. Veau’s classification
CLASS I
• Defect of soft palate only
CLASS II
• Defects involving hard and soft palate
CLASS III
• Defects involving hard palate to the alveolus
usually involving lip
CLASS IV
• Complete bilateral cleft
69
71. Pharyngeal obturator
A pharyngeal obturator prosthesis, which may also be called speech aid or
speech bulb prosthesis , extends beyond the residual soft palate to create
separation between the oropharynx and nasopharynx.
It provides a fixed structure against which the pharyngeal muscles can function
to effect palatopharyngeal closure.
71
72. MEATUS OBTURATOR
A meatus obturator is designed to close the posterior nasal choncae through a
vertical extension form the distal aspect of the maxillary prosthesis.
Indication : The entire soft palate has been lost in an edentulous patient.
Such a design will reduce leverage factors on the pharyngeal muscles against it.
The meatus obturator is often thought to be mechanical, whereas the fixed
horizontal pharyngeal obturator is thought to be more physiologic
72
73. FEEDING OBTURATORs
Prosthetic aid that is designed to close the cleft & provide the separation between
oral & nasal cavities & is used in infancy period.
Helps in following :
1. Feeding
2. Reduces nasal regurgitation.
3. Prevents tongue from entering the defect.
4. Allows spontaneous growth of palatal shelves
5. Speech development
73
74. Palatal lift prosthesis (PLP)
The concept of a PLP was described by Gibbons and Bloomer, Beder et al, and
Gonzalez and Aronson to improve soft palate dysfunction.
The PLP places the soft palate in contact with the lateral and posterior
pharyngeal walls to prevent nasal air escape during speech and prevent
regurgitation of food and liquid during swallowing.
Indications –
1. Speech disorders
2. Neurologic disorders
74
75. Fabrication of palatal lift appliance
Premkumar S. Clinical application of palatal lift appliance in velopharyngeal incompetence. J Indian Soc Pedod Prev Dent 2011;29, Suppl
S1:70-3
75
80. Tongue prosthesis
A total glossectomy or laryngectomy results in loss of basic vital
function
In these patients fabrication of a mandibular tongue prosthesis can
be done
Tongue prosthesis can be made for
Swallowing
Speech
80
83. The Use Of Swallowing In Making Complete Denture
Lower Impressions
The neuro musculature of the oral cavity provides a physiologic
adjunct for molding the lingual and buccal flanges and the posterior
borders of impressions for lower dentures
The most extreme movements of the posterior part of the floor of the
mouth occur during swallowing.
83
84. Buccal and labial borders of the impression are established by
manipulation of the lips and cheeks
Shape of the buccinator muscle is recorded in a nonfunctional
displaced position
Anterior part of the lingual border is recorded by asking the patient
to lick the upper lip with the tip of the tongue by gently moving the
tip from side to side
84
85. The most posterior lingual region, the hyoglossus muscle presses
against the passive lateral wall of the retro mylohyoid space
The posterior part of the mylohyoid muscle raises medially and
upward, thereby molding the lingual flange anterior to the retro
mylohyoid space
anterior part of the mylohyoid muscle molds the anterior part of the
border of the lingual flange resulting in classical S-shaped curve
85
87. Palatal augmentation prosthesis (PAP) can improve
swallowing function for the patients in rehabilitation
hospital
Aim - To clarify the effects of fitting palatal augmentation prosthesis
(PAP) on the swallowing function for the patients in rehabilitation
hospital
87
88. Material and Methods
The subjects included18 elderly hospitalized patients whose BMI
was<18.5 kg/m2
All subjects wore maxillary complete denture
During a video fluoroscopic examination the patients were asked to
swallow, post-swallowing pyriform sinus residue was detected
The subjects’ maxillary dentures were then modified into PAPs by
recording tongue movement in the palatal region
The resulting swallowing dynamics were evaluated qualitatively and
quantitatively before and after fitting the PAP
88
90. Results of this study showed that PAPs could be beneficial as
treatment devices for reducing post-swallowing pyriform sinus
residue formation due to decreased muscle strength
PAP fittings resulted in the resolution of aspiration of yogurt in two
patients and elimination of pharyngeal residue in three
PDT and PTT were significantly shortened with PAP
90
92. Conclusion
Tongue plays a key role in bolus formation and transfer to the pharynx
because tongue pressure generates the pharyngeal squeezing pressure
This study suggested that PAP fitting causes more intense contact between
the tongue and palatal region, thus reducing PTT.
These results demonstrated that PAPs could be beneficial treatment
devices that may reduce post-swallowing pharyngeal residue formation
due to decreased muscle strength.
92
93. Learning Outcome
Deglutition is an important physiological process for proper growth
and development of an individual
The inter-relationship between mastication, deglutition, respiration
and speech are complex
A thorough knowledge about this process can help us in, diagnosing,
treating and in rehabilitation of patients with deglutition difficulty
93
94. References
Guyton and Hall Textbook Of Medical Physiology 13th e
Wildman A, Fletcher S, Cox B. Patterns of Deglutition. Angle
Orthod 1964; 34(4):271-291
Winkler S. Essentials of Complete Denture Prosthodontics . 2nd
edition
Taylor Clinical Maxillofacial Prosthesis .3rd Edition
94
95. Tandon S . Textbook Of Pedodontics .2nd Edition
Sowmya S , Sadakshari S , Ravi Mb, Gujjari A.Prosthodontic Care
Of Patients With Cleft .J Orofac Res 2013; 3(1):22-27
Premkumar S. Clinical application of palatal lift appliance in
velopharyngeal incompetence. J Indian Soc Pedod Prev Dent
2011;29, Suppl S1:70-3
Nanda A, Koli D, Sharma S, Suryavanshi S, Verma M. Alleviating
speech and deglutition: Role of a prosthodontist in multidisciplinary
management of velopharyngeal insufficiency. J Indian Prosthodont
Soc 2015;15:281-3
95
96. Balasubramaniam MK, Chidambaranathan AS, Shanmugam G, Tah
R. Rehabilitation of Glossectomy Cases with Tongue Prosthesis: A
Literature Review. J Clin Diagn Res. 2016 Feb;10(2):ZE01-4
Marmor D, Herbertson JE. The used of swallowing in making
complete denture impressions. J Prosthet Dent. 1968 Mar;
19(3):208-18.
Christopher L. B. Lavelle, Applied Oral Physiology 2e
96
Notas do Editor
pharyngeal stage, which is involuntary and constitutes passage of food through the pharynx into the oesophagus;
oesophageal stage, another involuntary phase that transports food from the pharynx to the
stomach
Temporalis, masseter and medial pterygoid
epithelial swallowing receptor areas all
around the opening of the pharynx, especially on the
tonsillar pillars, and impulses from these areas pass to the
brain stem
Most essential is the tight
approximation of the vocal cords, but the epiglottis
helps to prevent food from ever getting as far as
the vocal cords. Destruction of the vocal cords or
of the muscles that approximate them can cause
Strangulation
All these effects acting together prevent passage of food into the nose and trachea
This sphincter remains strongly contracted between swallows
To summarize the mechanics of the pharyngeal stage
of swallowing: The trachea is closed, the oesophagus is
opened, and a fast peristaltic wave initiated by the nervous
system of the pharynx forces the bolus of food into the
upper oesophagus, with the
areas in the medulla and
lower pons that control swallowing are collectively called
the deglutition or swallowing cente
Primary peristaltic wave passes all the way from the pharynx to the stomach in about 8 to 10 seconds
Alter shape of the tongue.
The attachment of the genioglossi to the genial tubercles prevents the tongue from sinking back and obstructing respiration
Safety muscle of tongue
More the acute angle , more muscle activity to achieve velopharyngeal closure
More the soft palate displaced in function , less it is covered by denture base
More resorbed ridges , difficult in determination of palatal configuration
3 Muscles are running longitudinally.
Point 1 Imp to distinguish between vomiting & regurgitation Associated symptoms: abdominal pain, fever, diarrhoea.
To prevent this, there is apnoea along with approximation of vocal cords , forward & upward movement of larynx & backward movement of epiglottis to close the larynx.
More the acute angle , more muscle activity to achieve velopharyngeal closure
More the soft palate displaced in function , less it is covered by denture base
More resorbed ridges , difficult in determination of palatal configuration
Largest group of patients with soft palate defects include congenital clefts which are surgically treated but sometimes when surgical intervention doesn’t fulfil the demands prosthetic rehabilitation is done.
Obturators means shut off or close from obturate
Main aim – control nasal emission during speech & prevent leakage of material into nasal passage during deglutition
Levator veli palatini & superior constrictor plays a very major role in palatopharyngeal closure.
.
affecting the oropharyngeal mechanism in whom the anatomy remains normal but, the musculature either no longer functions or functions at a reduced level of activity.
9 yr old female reported with hypernasality & disarticulation , history revealed cleft lip & palate
Thus these help in lifting the soft palate the residual muscle activity in the pharyngeal walls will cause reduction in palatopharyngeal opening with decreased nasality.
Excessive anterior movement of the tongue tends to shorten the anterior part of the lingual flange.