chewing and swallowing interactive session

Question 1

the stages of mastication

Answer 1

1. incision - anterior teeth
2. food transferred to posterior teeth
3. numerous chewing cycles - three stages for each cycle

Question 2

what is the first of the chewing cycles?

Answer 2

opening stroke

Question 3

what happens during the opening stroke?

Answer 3

mandible lowered and moved laterally to working side
bolus held in place by cheeks and tongue

Question 4

what is the second of the chewing cycles?

Answer 4

closing stroke

Question 5

what happens during the closing stroke?

Answer 5

mandible elevated, deviates to working side

Question 6

what is the third of the chewing cycles?

Answer 6

power stroke

Question 7

what happens during the power stroke?

Answer 7

mandible moved back to midline so lower teeth glide on upper teeth

Question 8

which muscles are used in the opening stroke?

Answer 8

lateral pterygoids - both to protrude then more on balancing side to deviate to working side
suprahyoids (depress mandible)
infrahyoids (stabilize hyoid)

Question 9

which muscles are used in the closing stroke?

Answer 9

medial pterygoids
masseters
temporalis
lateral pterygoid (balancing side)

Question 10

which muscles are used in the power stroke?

Answer 10

masseter
medial pterygoid
temporalis
lateral pterygoid (working side)

Question 11

swallowing has how many stages?

Answer 11

three

Question 12

what are the three stages of swallowing?

Answer 12

oral phase
pharyngeal phase
oesophageal phase

Question 13

is the oral phase voluntary or no

Answer 13

yes

Question 14

what happens in the oral phase?

Answer 14

lips brought together and teeth occluded
bolus formed
bolus moved into oropharynx
oropharyngeal seal established

Question 15

what happens in the pharyngeal phase?

Answer 15

velopharyngeal (nasopharyngeal) seal established
pharynx shortened and widened, larynx elevated
laryngeal inlet narrowed and glottis closed
bolus moved through pharynx

Question 16

is the pharyngeal phase voluntary?

Answer 16

no

Question 17

is the oesophageal phase voluntary?

Answer 17

no

Question 18

what happens in the oesophageal phase?

Answer 18

bolus moved into stomach
respiratory passage opened again
larynx repositioned

Question 19

to occlude the teeth, what muscles are involved?

Answer 19

masseter
temporalis
medial pterygoid

Question 20

oral phase - what muscles?

Answer 20

hyoid bone - elevation of this bone raises tongue to roof and presses bolus against the hard palate
mylohyoid
anterior and posterior digastric muscles
genioglossus (forms trough - tongue)
styloglossus - sides of tongue elevate to assist in trough formation

Question 21

what muscles to move bolus into oropharynx

Answer 21

genioglossus - tip of tongue pressed against maxillary incisors and hard palate
styloglossus - tongue retracted and bolus dragged posteriorly
palatoglossus - oropharyngeal isthmus sealed

Question 22

which muscles pharyngeal phase

Answer 22

superior constrictor and fibres of palatopharyngeal muscle - passavant’s ridge exaggerated
superior constrictor
middle constrictor
inferior constrictor

Question 23

muscles used in the oesophageal phase

Answer 23

peristalsis of oesophageal wall
relaxation of lingual, pharyngeal, and laryngeal muscles
infrahyoid muscles - thyrohyoid, sternohyoid, sternothyriod, and omohyoid
hyoglossus, genioglossus

Question 24

dysphagia

Answer 24

abnormal swallowing behaviour

Question 25

consequences of abnormal swallowing behaviour

Answer 25

social - embarrassment
dehydration + malnutrition
aspiration - asphyxiation or pneumonia

Question 26

two types of dysphagia

Answer 26

obstructive, pathophysiological

Question 27

two types of obstructive dysphagia

Answer 27

intrinsic - within tract
extrinsic - outside tract

Question 28

types of pathophysiological dysphagia

Answer 28

xerostomia - dry mouth (problem w salivary glands)
neurological
(cerebrovascular accident, MS, parkinson’s, brain tumour, head injury, motor neuron disease)