oral function Flashcards
4 correlating stages in the feeding sequence (before swallowing).
- ingestion - biting
- stage one transport - moving material from the front to the level of the posterior teeth
- mechanical processing - broken down and mixed with saliva
- stage two transport - bolus moved back
Function of facial muscles in feeding
facial muscles help to control food bolus and prevent spillage:
-orbicularis oris
-buccinator
What considerations should be made regarding the tongue when setting posterior teeth in a RPD.
inaccurate placement of mandibular posterior teeth might interfere with tongue’s movements and will compromise retention and stability of the denture
Four mechanisms which prevent reflux during swallowing.
elevation of the soft palate
sides of the tongue contacts pillars of faces
dorsum of the tongue contacts posterior pharyngeal wall
upper oesophageal sphincter = reflux from oesophagus into pharynx
lower oesophageal sphincter = reflux from stomach into oesophagus
Muscles involved in food processing, list 4 main types?
muscles of mastication = temporalis, masseter, lateral and medial pterygoid
suprahyoid (digastric, stylohyoid, mylohyoid and geniohyoid muscles)
infrahyoid (sternohyoid, sternothyroid, thyrohyoid and omohyoid )
tongue muscles (intrinsic and extrinsic)
movements that occur during chewing process, list and describe?
Opening: The jaw opens to allow food to enter the mouth.
Closing: The jaw closes to grip and compress the food between the teeth.
Lateral movement: The jaw moves from side to side to grind the food between the molars.
Vertical movement: The jaw moves up and down to break down the food and mix it with saliva.
Tongue movement: The tongue helps to move food around the mouth and push it between the teeth for grinding.
Cheek movement: The cheeks help to keep food between the teeth during grinding.
Saliva production: Saliva is produced in the mouth to moisten the food and aid in digestion.
occlusal phase (mandible is stationary/teeth are joined)
opening phase (jaw depressor muscles are active)
closing phase (jaw elevator muscles are active)
what muscles are responsible for changing shape and position of tongue and name them?
intrinsic = alter shape only = longitudinal, vertical, transverse
extrinsic = alter shape and position =
genioglossus
hyoglossus
palatoglossus
styloglossus
What are the 4 muscles of mastication
temporalis
masseter
lateral and medial pterygoid
Mouth movement during mastication (2)
i. What is the diagram called
ii. What does it show
posselt’s envelope of motion
refers to the range of motion of the mandible
saggital view of maximum mandibular movement
What are the tmj jaw movements
rotation - initial opening
translation - wider opening
What are the intrinsic tongue muscles and there role
intrinsic muscles alter the shape of the tongue
longitudinal
vertical
transverse
What are the extrinsic tongue muscles and there role
alter shape and position within the oral cavity of the tongue
genioglossus
hyoglossus
palatoglossus
styloglossus
Physiological and psychological reason of keeping PDL for dentures
PDL acts as a shock absorber, distributing forces equally
PDL helps to maintain shape and density of alveolar bone
keeping the PDL can provide a sense of continuity and familiarity.
patients may also experience a psychological benefit from the tactile sensation of the PDL, which can help them feel more connected to their denture and improve their ability to chew and speak.
What are the muscles that control mandibular movement?
masseter = closing the jaw and elevation of the mandible
temporalis = closing the jaw and retraction of mandible
medial pterygoid = elevates the mandible
lateral pterygoid = protrusion, depression of mandible
Describe the movements of the Temporomandibular Joint (TMJ)
ROTATION = initial opening = hinge
TRANSLATION = wider opening = protrusive or retrusive