Anatomy of the Upper GI Tract Flashcards
What are the 4 functions of the upper GI tract?
Mastication
Deglutition
Taste
Salivation
What are the 4 structures involved in mastication?
Upper teeth of maxilla
Lower teeth of mandible
Tongue
Buccinator muscle (cheek muscle)
What is the function of mastication?
Chops food increasing surface area which facilitates taste and beginning of digestion
What are the components of the adult dentition?
4 quadrants, each containing: 2 incisors (1 & 2) 1 canine (3) 2 premolars (4 & 5) 3 molars (6, 7 & 8)0 (32 in total)
what does the temporomandibular joint consist of?
Temporal bone has a mandibular fossa where head of condylar process of mandible sits
what 4 muscles control the opening and closing of the TMJ?
What nerve supplies them?
Temporalis major = closes (over temples) Masseter = closes (jaw) Medial pterygoid = closes (vertical) Lateral Pterygoid = opens (horizontal) All supplied by CN V3 (mandibular division of the trigeminal nerve)
what are the 2 cavities of the TMJ and what separates them?
superior cavity for translation
Inferior cavity for rotation
Separated by articular disc
what is the function of the lateral pterygoid?
pulls the articular disc forward, increasing the size of the superior and inferior cavity cavity
describe the course of CN V3
originates in the pons
travels through foramen ovale
travels to muscles of mastication and sensory area
does the mandibular division of the trigeminal nerve (CN V3) contain both sensory and motor fibres?
yes
why might you ask a patient about their dental health or if they have any loose or loose arts of teeth?
poses a choking hazard and aspiration risk as well as infection risk
what is the position and function of the posterior 1/3rd of the tongue?
sits vertically in the oropharynx
involved in taste and general sensation (CNIX)
what is the position and function of the anterior 2/3rds of the tongue?
sits horizontally in the oral cavity
involved in taste (CNVII) and general sensation (CNV3)
what are the 4 types of papillae in the tongue and where are they?
Foliate = towards the back on the sides
Vallate = v shaped, at division between posterior/anterior
Fungiform (taste buds) = over mid tongue
Filiform = tip of tongue
what is the route of the facial nerve?
arises from the pontomedullary junction travels through the temporal bone via the internal acoustic meatus, then the stylomastoid foramen Goes on to supply: anterior 2/3rds of tongue muscles of facial expression glands in floor of mouth