Deglutition and its importance in Prosthodontics

1. DEGLUTITION
Dr. Shubham Parmar
1st Year MDS
Department Of Prosthodontics
1

2. Contents
 Introduction
 Components of deglutition
 Theories of deglutition
 Stages of deglutition
 Muscles associated with deglutition
 Gag Reflex
2

3.  Applied physiology
 Prosthodontic considerations
3

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

9. 9

10. Theories Of Deglutition
10

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

15. Stages of deglutition
15
Oral
Pharyngeal
Oesophageal

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

28. Muscle of Tongue
28

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

30. 30

31. Extrinsic muscles
31

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

36. Muscles of Soft Palate
36

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

38. 38

39. Arterial supply
 Levator and Tensor veli Palatini
ascending palatine branch of facial artery
greater palatine branch of maxillary artery.
 Palatoglossus
ascending palatine branch of facial artery
ascending pharyngeal artery.
 Palatopharyngeus
ascending palatine branch of facial artery
greater palatine branch of maxillary artery
ascending pharyngeal artery
39

40. Pharynx
40

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

42. 42

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

48. Longitudinal Muscle of Pharynx 48

49. Applied Physiology
 Dysphagia
 Odynophagia
 Globus hystericus
 Phagophobia
 Vomiting
 Deglutition apnoea
49

50.  Aspiration
 Cricopharyngeal Dysfunction
 Choking
 Antiperistalsis
 Presbyphagia
 Gag reflex
50

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

59. Antiperistalsis
59
Wave of contraction in digestive tract that moves toward the oral
end of tract -regurgitation

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

65. 65
Prosthodontic Consideration

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

70. Management of soft palate defects
 Obturator prosthesis :
1. Pharyngeal obturator.
2. Meatus prosthesis.
3. Feeding obturators.
 Palatal lift prosthesis.
70

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

76. 76

77. 77

78. 78

79. 79

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

81. 81

82. 82

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

86. Review Articles
86

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

89. 89

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

91. 91

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