Swallowing Subphases Flashcards
Oral Prep 1:
Function- ingested material brought into oral cavity and contained there
Lips involved in grasping, sucking, and forming anterior oral seal; teeth and cheeks also involved
Important to prevent food from spilling out
- Oral prep - Phase 2
Function= bolus formation
Structure
-jaw moves in a “rotary lateral” pattern in mastication
-tongue positions material between occlusal surfaces of teeth
-buccal tone prevents spillage of bolus into lateral sulci
-saliva has several functions: chemical breakdown of ingested material, lubrication of material, promotes oral hygiene
Oral Prep Phase 3
Function= bolus containment
bolus is contained between tongue and hard palate
tongue tip contacts alveolar ridge to contain bolus anteriorly
superior tongue surface contains bolus inferiorly
lateral tongue margins contact maxillary teeth to contain bolus laterally
posterior tongue contacts soft palate to contain bolus posteriorly, forming the retro-oral seal
Oral Transport Phase 1
Function= bolus is transported posteriorly by tongue
Structure
bolus is squeezed posteriorly between superior surface of tongue and hard palate by tongue “stripping wave” action
Oral Transport Phase 2
function= tongue loading
Structures
soft palate elevates and posterior tongue lowers, breaking retro-oral seal
superior tongue surface forms a central groove
tongue dorsum moves inferiorly and anteriorly, loading the bolus on its surface
- Oral Transport – Phase 3
Function 3
pharyngeal stage of swallow is triggered
Structures
bolus stimulates sensory receptors lining anterior faucial pillars, tongue base, and posterior pharyngeal wall
- Pharyngeal – Phase 1
Function 1
formation of velopharyngeal seal
Structures
soft palate (velum) contacts posterior pharyngeal wall
Pharyngeal Phase 2
Function= tongue propels bolus into pharynx
Structures
mandible is stabilized
posterior tongue makes a piston-like motion that drives the bolus through the pharynx
- Pharyngeal – Phase 3
Function= laryngeal closure
Structures
larynx closes in an inferior to superior direction
true vocal fold closure
false vocal fold closure
arytenoid cartilages to epiglottic base
deflection of the epiglottis
Pharyngeal Phase 4
Function= hyolaryngeal elevation/excursion
Structures
hyoid elevates and moves anteriorly, pulling thyroid cartilage with it
once hyoid reaches maximal elevation, thyroid cartilage continues to elevate due to contraction of thyrohyoid muscle
Pharyngeal - Phase 5
Function 5
epiglottic deflection;
(a) allows bolus to empty out of valleculae,
(b) directs bolus laterally toward pyriform sinuses, away from laryngeal vestibule
Structures
epiglottis deflects to horizontal
mechanical forces of laryngeal elevation
epiglottis deflects below horizontal
active muscle forces (aryepiglotticus & thyroepiglotticus m.)
traction from anterior movement of hyoid (lateral hyoepiglottic ligaments)
Pharyngeal Phase 6
Function 6= opening of Upper Esophageal Sphincter (UES) allows entry of bolus into esophagus
Structures
UES is comprised principally of the cricopharyngeus muscle
during swallowing, UES opens due to:
relaxation of cricopharyngeus
traction by anterior/superior movement of hyo-laryngeal complex
outward pressure exerted by bolus itself (intrabolus pressure)
Pharyngeal - Phase 7
Function 7
bolus is cleared from the pharynx
Structures
bolus clearance:
propagated contraction of pharyngeal constrictors (peristalsis)
shortening of pharynx
Esophageal Phase
Function
bolus transport from pharynx to stomach
Structures
primary peristalsis - progression of a peristaltic contraction along the esophagus in coordination with relaxation of UES and LES
secondary peristalsis - peristalsis initiated by intraesophageal distention (e.g., material from a previous swallow, gastric reflux)
