Oral cavity Flashcards
Oral region
OC (mouth), teeth, gums, tongue, palate, and region of palatine tonsils
- 2 parts of OC: oral vestibule and oral cavity proper
- Oral fissure size controlled by orbicularis oris
- Boundaries of OC proper: L and A -
upper and lower dental arcades, roof – palate, P communication w/oropharynx
Palate
Arched roof of OC proper and floor of NCs
- Bony hard part A, soft tissue segment P
- HP: formed by parts of maxillae and palatine bones; covered by a mucous membrane; filled w/tongue at rest
Soft palate
Movable P 1/3 of palate: aponeurotic A
and muscular P
- Extends PL, curved free margin w/conical process: uvula.
- L, SP is continuous w/wall of pharynx, jointed to both tongue & pharynx by
palatoglossal and palatopharyngeal arches
SP muscles
from cranial base, descend towards palate.
- SP may be elevated and come into contact w/P pharyngeal wall, thus sealing off oral passage from nasopharynx during
swallowing or breathing through mouth, palate can also be drawn I, sealing off OC from nasal passage (when breathing through nose w/open mouth)
SP muscle names
Tensor veli palatini: tenses SP, opens pharyngotympanic tube when swallowing and yawning
Levator veli palatini: elevates palate
during swallowing and yawning
Palatoglossus: elevates P tongue
Palatopharyngeus: tenses SP, pulls pharynx during swallowing
Musculus uvulae- shortens, pulls uvula S
Tongue
mobile muscular organ found partly in OC proper, partly in oropharynx
- Mainly composed of muscles, covered by mucous membrane
- Functions: assists in mastication, taste, swallowing, speech, oral cleaning
Tongue muscles
Extrinsic tongue muscles alter position of tongue, intrinsic ones regulate its shape
- 4 extrinsic muscles: genioglossus, hyoglossus, styloglossus, palatoglossus
- Intrinsic tongue muscles (longitudinal, transverse, and vertical)
Tongue innervation
tongue muscles are supplied by CN XII, palatoglossus (SP muscle, pharyngeal nerve plexus of CN X)
Salivary glands
large parotid, submandibular, and sublingual glands, small accessory salivary glands scattered over palate, lips, cheeks, tonsils, tongue
- Functions: keep oral mucous membranes moist, lubricate food during mastication, begin starch digestion, preventing tooth decay, support ability to taste
Temporalis
elevates mandible, closing jaw, retracts mandible
Masseter
elevates mandible; helps protrude
mandible
L pterygoid
acting bilaterally, protracts mandible and depresses chin, acting unilaterally, swings jaw to contralateral side
M pterygoid
acts w/masseter to elevate mandible, assists in protrusion, all tongue muscles: CN V3
General sensory
V2 – oral mucosa
V3 – oral mucosa
IX - palatine tonsil, soft palate, and 1/3 of tongue
Visceral sensory
X – I pharynx and larynx mucosa
Motor
V3 – Muscles of mastication
VII – Muscles of facial expression
IX – Stylopharyngeus m. – pharynx muscle
X – Muscles of pharynx, larynx and palate + palatoglossus
XII – Muscles of tongue (minus palatoglossus)
Visceral motor
VII – Salivary glands
IX – Parotid gland
Special sense
VII – A 2/3s of tongue
IX – P 1/3 of tongue
X – epiglottis and root of tongue
