Stages of swallowing

short description of the process of deglutation with all the stages and their complete description and graphic view of all the things that are undergoing during the process of swallowing including an animated summary of whatever goes in the mouth for ease of understanding.

1. Stages Of Swallowing
Under The Guidance of: Submitted by:
Dr. N.N.Singh Satyaki Verma
Dr. Ambika Choudhary BDS- I Year

2. Contents
Introduction
Deglutition
Oral Phase
Pharyngeal Phase
Esophageal Phase

3. Introduction
Deglutition is the act of swallowing, through
which a food or liquid bolus is transported
from the mouth through the pharynx and
esophagus into the stomach.

4. Deglutition
Deglutition is a smooth
coordinated process that
involves a complex series of
voluntary and involuntary
neuromuscular contractions
and typically is divided into
three distinct phases:
Oral
Pharyngeal
Esophageal

5. Oral Phase
Total swallow time from oral cavity to stomach is no
more than 20 seconds
The process begins with contractions of the tongue
and striated muscles of mastication.
In the oral phase, a formed bolus is positioned in the
middle of the tongue. The bolus is then pressed
firmly against the tonsillar pillars, triggering the
pharyngeal phase.
The cerebellum controls output for the motor nuclei of
cranial nerves V (trigeminal), VII (facial), and XII
(hypoglossal).

7. Pharyngeal Phase
The pharyngeal phase of swallowing is the shortest
but is the most complex.
In this phase the soft palate elevates closing off the
nasopharynx and preventing Nasopharyngeal
regurgitation.
When the pharyngeal phase begins, other activities
such as chewing, breathing, coughing and vomiting
are concomitantly inhibited.
Closure of the nasopharynx

8. Pharyngeal Phase
The pharynx prepares to receive the bolus
Opening of the auditory tube
Opening of the auditory tube
Closure of the oropharynx
Laryngeal closure
Hyoid elevation
Bolus transits pharynx

10. Esophageal phase
The bolus is propelled about 25 cm from the
cricopharyngeus through the thoracic esophagus via
peristaltic contractions.
The bolus is propelled downwards at a rate of 3–
5 cm/s.
The lower esophageal sphincter relaxes and the
bolus moves into the gastric cardia.

13. Summary