3. Oral preparatory stage
• Not required for liquids
• Solid food chewed, lubricated with saliva &
converted to a bolus
• Requires coordinated movement of lips, cheeks,
jaws & tongue against a closed oropharyngeal
isthmus
5. Oral propulsive stage
• Food bolus propelled backwards by pressing
of tongue against hard palate
• Approximation of tongue against hard palate
starts with tip of tongue & moves back
• Stage ends when food bolus crosses anterior
tonsillar pillar
12. Pharyngeal stage
5. Posterior retraction of base tongue:
tongue driving
force
6. Pharyngeal constrictors contract
7. Elevation of pharynx
8. Opening of cricopharyngeal sphincter