Oral Functions - Swallowing Flashcards
What are the 3 stages of swallowing
Buccal phase (voluntary) Pharyngeal phase (involuntary) Oesophageal phase (involuntary)
What are the 2 functions of swallowing
Feeding and protection
Why is swallowing potentially dangerous
The foodway crosses the airway
Describe how liquids are swallowed
Liquids are gathered on the tongue, anterior to the pillars of the fauces
The mouth is separated from the pharynx by a posterior oral seal
The liquid bolus is propelled through the oropharynx and hypopharynx into the oesophagus
Describe how a solid is swallowed
Chewed food accumulates on the pharyngeal part of the tongue and oropharynx
The bolus is propelled through the hypopharynx and into the oesophagus
What is the main difference in how liquids and solids are swallowed
Liquids are swallowed from the mouth and there is a true oral seal
Solids are swallowed from the oropharynx and there is no oral seal
Describe the squeezeback movement
The forward movement of the tongue during the occlusal and initial opening phases creates a contact between the tongue and the hard palate
The contact moves backwards, squeezing the processed food through the fauces
What events occur during swallowing
Propulsion of food
Prevention of reflux
Protecting the airway
How does the duration of mastication vary
Varies with food consistency
What is in place to prevent reflux
Elevation of the soft palate
Tongue sides contact pillars of fauces
Tongue dorsum contacts posterior pharyngeal wall
Upper and lower oesophageal sphincters
How can stomach acid cause erosion
Through reflux, vomiting, regurgitation and rumination
What is the most common cause of palatal surface erosion
Stomach acid - 2/3 of cases
What is attrition
Tooth wear occlusally caused by contact between occluding teeth (bruxism/parafunction)
The teeth inter-digitate indicating that attrition is occurring
What is abrasion
Either caused by biting or chewing objects between the teeth eg - tobacco pipes, nails or pens
OR
Most commonly a combined lesion involving erosion and abrasion
How can acids cause abrasion
Acids weaken the outer 3-5 microns of mineralised tissue and increase the susceptibility of the enamel and dentine to abrasion from tooth brushing
