Deglutition with Nervous control and Applied aspects

Deglutition

1. Deglutition

2. Deglutition:Deglutition:
Deglutition is a French word which evolved from latin Deglutition is a French word which evolved from latin
“deglutir (to swallow down) related to “deglutir (to swallow down) related to
“glutton”(someone who eats too much)“glutton”(someone who eats too much)
It is a complex of reflex actions which involves
modes of transport of material from the mouth to
esophagus.
True reflex

3. It involves the movement of the bolus from mouth to
stomach
It involves:
Raising of the soft palate to close off the
nasopharynx.
Raising of the larynx to close off the laryngopharynx.
Thus a protective reflex

4. TYPES OF SWALLOWTYPES OF SWALLOW
Swallow inSwallow in
UteroUtero
InfantileInfantile
swallowswallow
AdultAdult
swallowswallow

5. Deglutition in AdultsDeglutition in Adults
Solid Food Liquid Food
Solid Swallowing
•It has three phases
 ORAL – Voluntary stage
 PHARYNGEAL
 OESOPHAGAL
Reflex stages

6. Deglutition [LIVE]Deglutition [LIVE]

7. •This phase is divided into the
following 2 parts:
•Oral preparatory phase
–Moulding of food and saliva into
a bolus
–Achived by acion of oral
receptors to masticatory
pattern generator via
mandibular nerve.
•Efferent from trigeminal
motor
Oral phaseOral phase

8. •Oral transit phase
–.
–This process requires that a labial seal be
maintained to prevent food from leaking.
–Moulded bolus moved backwards.
–Infants-wave of contraction produced by
moving tongue against hard palate.
–Adults-bringing teeth in centric occlusion.
.

9. Pharyngeal phasePharyngeal phase
•This phase, a reflex action in
which the bolus moves
through the pharynx, takes
place in less than 1 second.
•Protective phase.
•Protects airways, blocks
respiration.
•Soft palate elevates and seals
off nasal cavity.

10. ●This stage is followed by pushing of
the bolus further into the pharynx
toward the cricopharyngeal
sphincter by the pharyngeal
constrictor muscles.
● The phase ends with the elevation
of the larynx itself, which also helps
in the cricopharyngeal opening by
stretching that region.
●This action is followed by relaxation
of the cricopharyngeal muscle,
allowing the bolus to pass into the
esophagus.

11. EsophagealEsophageal phasephase
•This final phase of the
swallowing process is under
the control of the brain stem
and the myenteric plexus.
• A peristaltic wave beginning
in the pharynx pushes the
bolus sequentially from the
cervical esophagus down
through the esophageal-
gastric sphincter into the
stomach.
•Respiration restablished
with inspiration.
•Relaxation allows food 2
pass into stomach.

12. ORAL PHASE

13. PHARYNGEAL PHASE

14. Deglutition (Swallowing)Deglutition (Swallowing)
(a) Upper esophageal
sphincter contracted
(b) Upper esophageal
sphincter relaxed
(c) Upper esophageal
sphincter contracted
(e)(d)
Bolus of
food
Uvula
Bolus
Relaxed musclesRelaxed
muscles
Tongue
Pharynx
Epiglottis
Glottis
Trachea
Bolus
Epiglottis
Bolus of food
Longitudinal muscles
contract, shortening
passageway ahead of bolus
Gastroesophageal
sphincter closed
Circular muscles
contract, constricting
passageway and pushing
bolus down
Stomach
Gastroesophageal
sphincter open
Esophagus

15. Abnormality at the oral stageAbnormality at the oral stage
•Improper lip seal.
•Inflammation of the tonguefrom any cause may
interfere with the phase of swallowing called oral
dysphagias.

16. Abnormality at the pharyngeal stageAbnormality at the pharyngeal stage
•Swallowing problems occur when the nasal cavity
cant be sealed from oropharynx.
•Patients with palatal clefts and patients with
paralysis.
•Hence food and liquid enter the nasal cavity when
trying to swallow.

17. Abnormality at the esophageal phaseAbnormality at the esophageal phase
defects in the wall of the esophagus or in the
external structures (eg, in the hilar lymph
nodes) can lead to dysfunction in the
propulsion of the bolus within the esophagus
on to the stomach (eg, esophageal webs,
rings, strictures; intraluminal obstruction
from solids)

18. Liquid FoodLiquid Food
•In case oral cavity and oesophagus are present in a
straight pathway. It is possible to ingest fluids without
any oral activity.
Dynamics
•Cricopharyngeal sphincter at the end of oesophagus
ends up being functional rather than anatomical.
•Despite absence of swallowing activity tongue makes
wave like movements assisting in liquid passage.

19. Stages
•Tongue hollowed at tip but raised posteriorly - it helps in accumulation of
fluid in anterior part of oral cavity.
•Raising of tip of tongue to touch palate – to create wave like contraction
and hence initiating phargyngeal phase of swallowing.
Pharyngeal phase
•Sealing of nasopharynx – by raising the soft palate to contact the
pharyngeal wall and the adenoidal pad.
•Raising of larynx – so the fluid is deflected away from it by flowing on
either side of the epiglottis into the stomach.

20. Nervous control of swallowingNervous control of swallowing
•Deglutition is usually initiated by sensory
impulses transmitted as a result of
stimulation of receptors on
 Fauces
 Tonsils
 Soft palate
 Base of tongue
 Posterior pharyngeal wall
•Sensory impulses  6th, 9
th
, and 10
th

cranial nerves
•Efferent impulses 9, 10, 12
th
cranial

21. Thank you!Thank you!