Oral functions - feeding

Question 1

what are the components of the feeding sequence?

4

Answer 1

1. ingestion
2. transport
3. mechanical processing
4. food processing

Question 2

describe the ingestion stage of feeding

Answer 2

• movement of the food from the external environment into the mouth
• acomplished by biting and/or using tools

Question 3

what facial muscles help with controlling food bolus and spillage?

2

Answer 3

• buccinator
• orbicularis oris

Question 4

describe the transport stage of feeding

Answer 4

• moving food from the front of the mouth to the posterior teeth
• food is gathered on tongue tip
• tongue retracts, pulling material to the posterior teeth
• hyoid bone retracts and narrows oropharynx

Question 5

describe the mechanical processing stage of feeding

Answer 5

• solid foods are **broken down and mixed with saliva **
• most solid floods have fluids removed before transport and swallowing
• food is chewed by premolar and molar teeth
• some soft foods are squashed by tongue on hard palate

Question 6

what muscles are involved and co-ordinated in food processing?

4

Answer 6

• mandiular muscles
• suprahyoid muscles
• tongue muscles
• lips and cheeks

Question 7

what are the mandibular muscles?

Answer 7

• temporalis
• masseter
• medial pyterygoid
• lateral pterygoid

Question 8

what are the suprahyoid muscles?

4

Answer 8

• digastric
• mylohyoid
• geniohyoid
• stylohyoid

Question 9

what are the intrinsic and extrinsic tongue muscles?

Answer 9

intrinsic
* longitudinal
* vertical
* transverse

extrinsic
* palatoglossus
* styloglossus
* genioglossus
* hyoglossus

Question 10

what are the actions of the tongue in chewing?

Answer 10

• controld the bolus
• gathers food and rotates to reposition the bolus on the occlusal table
• keeps bolus on chewing surfaces along with cheeks
• gathers bolus for transport

Question 11

what is the difference between swallowing solids and liquids?

Answer 11

• with solid foods, the mouth is continuous with the oropharynx
• with liquids, a posterior oral seal is produced

Question 12

describe the chewing cylce phases

Answer 12

• ICP (intercuspal/occlusal phase) - mandible is stationary / teeth are joined and maximum intercuspation is achieved to stabilise the mandible before mastication and swallowing
• opening phase - jaw depressor muscles are active (lateral pterygoid, anterior digastric, mylohyoid, inferior head of lateral pterygoid)
• closing phase - jaw elevator muscles are active (masseter, temporalis, medial pterygoid, superior belly of lateral pterygoid)

Question 13

if the occlusal surfaces of dentures are evenly worn flat, what does it suggest?

Answer 13

vertical mandibular movements

Question 13

what is a shortened dental arch (SDA)?

Answer 13

• 20 teeth considered the minimimum for acceptable masticatory function, aesthetics and maintenance of oral hygiene
• provides sufficient occlusal stability, comfort and appearance
• absent molar teeth are only replaced if absence gives rise to problems

Question 14

what are the three stages of swallowing?

Answer 14

1. buccal phase (voluntary)
2. pharyngeal phase (involuntary)
3. oesophageal phase (involuntary)

Question 15

which phases of swalloing are involuntary?

Answer 15

• pharyngeal phase
• oesophageal phase

Question 15

how is the airway protected when swallowing?

Answer 15

• upward and forward movement of the larynx
• closure of laryngeal inlet (epiglottic muscles, epiglottis)
• abduction of vocal folds
• stop breathing

Question 16

how is acid reflix prevented?

Answer 16

• elevation of soft palate
• tongue (sides) contacts pillars of fauces
• tongue (dorsum) contacts posterior pharyngeal wall
• upper oesophageal sphincter
• lower oesophageal sphincter