Oral Cavity Flashcards
The oral fissure, between the lips, is the entry to the mouth. The oral cavity is bounded laterally by the cheeks and extends posteriorly to the oropharyngeal isthmus.
The oral cavity is subdivided into two regions:
Vestibule – space between the lips/cheeks and the upper and lower alveolar ridges/teeth
Oral cavity proper –area “medial” to the alveolar ridge/teeth
The oral fissure, between the lips, is the entry to the mouth. The oral cavity is bounded laterally by the cheeks and extends posteriorly to the oropharyngeal isthmus.
The oral cavity is subdivided into two regions:
Vestibule – space between the lips/cheeks and the upper and lower alveolar ridges/teeth
Oral cavity proper –area “medial” to the alveolar ridge/teeth
What is the vascular supply and innervation to the Cheeks?
Vascular supply - branch of the maxillary artery
Innervation (sensory) – zygomaticofacial & infraorbital nerves (CN V2); buccal nerve (CN V3)
What is the vascular supply and innervation to the lips?
Vascular supply – superior & inferior labial branches of the facial artery
Innervation - infraorbital nerve (CN V2) and mental nerve (CN V3)
What is the orbicularis oris? What is its innervation?
orbicularis oris - sphincteric-functioning muscle surrounding the oral fissure
muscle of facial expression and innervated by CN VII.
What is the buccinator? Where is its orgin? What is its function? What is its innervation?
muscle of the cheek
originates from the pterygomandibular raphe, attaches to the outer alveolar surfaces of the maxilla and mandible and interdigitates with the obicularis oris
prevents food from accumulating in the vestibule by compressing the check against the teeth and gums: together with the tongue, it keeps food between the teeth during mastication
innervation - buccal branch of CN VII (muscle of facial expression)
What is the VESTIBULE? What is the Parotid Papilla? What are the Upper and Lower Labial Frenulae?
slit like “U” shaped space bordered by the lips/cheeks on the outside and the teeth/alveolar ridge on the inside
communicates with the oral cavity posterior to the last molar when teeth are occluded
parotid papilla - parotid ducts piece the buccinators and drain opposite the maxillary (upper jaw) second molar tooth
upper and lower labial frenulae - folds of mucosa attaching the lips to the gingiva (gums) in the median plane
What is the lingual frenulum?
a midline fold of mucosa going from the floor of the mouth to the inferior surface of the tongue near its base
What is the sublingual papilla (caruncle)?
opening of the submandibular salivary duct on each side of the lingual frenulum
What are the sublingual folds?
mucosa overlying the sublingual glands and submandibular ducts
extends posterolaterally from the sublingual papilla
What are the upper and lower labial frenulae?
located in the vestibule, folds of mucosa attaching the lips to the gingiva (gums) in the median plane
What is the origin/insertion of the mylohoid muscles?
What is the innervation of the mylohoid muscles?
What is the action of the mylohyoid muscles?
Origin/insertion
triangular-shaped muscles originating from the mylohyoid lines of the mandible
posterior fibers pass medially and downwards to insert on the body of the hyoid bone
from there the muscles come together and interdigitate in a midine raphe that extends from hyoid bone to the symphysis menti
Innervation – mylohyoid branch of the inferior alveolar nerve (CN V3)
Action
primarily elevates the floor of the mouth at the initiation of deglutition
depending upon which bone is “fixed”, depresses mandible to open the oral fissure or elevates hyoid bone during swallowing
What is the origin and insertion of the geniohyoid muscles?
What is the innervation of the geniohyoid muscle?
What is the action of the geniohyoid muscle?
Origin: inferior mental spines of mandible / insertion: body of hyoid
Innervation –branch of C 1 via hypoglossal nerve (CN XII)
Action
elevates and pulls the hyoid bone anteriorly during swallowing
when hyoid bone is fixed, depresses the mandible
What is the location of the Submandibular gland? What muscle does it loop around? What does its duct empy into and where?
The superficial part of the submandibular gland is located in the digastric triangle superficial to the mylohyoid muscle. Together with a small tongue of glandular tissue, the submandibular duct loops around the posterior free margin of the mylohyoid muscle. The duct continues anteriorly beneath the mucosa of the oral cavity proper to empty into a small submucosal caruncle, the sublingual papilla, just lateral to the frenulum of the tongue .
Where is the Sublingual gland?
The sublingual gland rests upon the mylohyoid muscle and numerous small excretory ducts drain on to the summit of the sublingual fold.
Whereas the parotid ducts drain into the vestibule, both the submandibular and sublingual glands drain into the oral cavity proper.
Salivary glands (parotid gland not included in this discussion; lacrimal gland is an exception)
parasympathetic innervation to the glands lying:
superior to the oral fissure arrives via the ______ ganglion
inferior to the fissure arrives via the ______ ganglion
sympathetic innervation
superior to the oral fissure follows pathway of ______ carotid vessels
inferior to the fissure follows pathway of ______ carotid vessels
parasympathetic innervation to the glands lying:
superior to the oral fissure arrives via the pterygopalatine ganglion
inferior to the fissure arrives via the submandibular ganglion
sympathetic innervation
superior to the oral fissure follows pathway of internal carotid vessels
inferior to the fissure follows pathway of external carotid vessels
See Slides 10 through 12 Oral Cavity SBQs for innervation and ganglion permutations of the oral cavity.
See Slides 10 through 12 Oral Cavity SBQs for innervation and ganglion permutations of the oral cavity.
Autonomic innervation
All postganglionic parasympathetic fibers of the head are distributed by hitching a ride on the pathways of one of the three main branches of the trigeminal nerve – V1, V2, V3.
All postganglionic sympathetic fibers of the head that go to specific targets (i.e. lacrimal gland) hitch a ride on the pathways of one of the three main branches of the trigeminal nerve – V1, V2, V3.
Autonomic innervation
All postganglionic parasympathetic fibers of the head are distributed by hitching a ride on the pathways of one of the three main branches of the trigeminal nerve – V1, V2, V3.
All postganglionic sympathetic fibers of the head that go to specific targets (i.e. lacrimal gland) hitch a ride on the pathways of one of the three main branches of the trigeminal nerve – V1, V2, V3.
Parasympathetic innervation
(secretomotor)
Whichtwo para nerve uses the
Pterygopalatine ganglion?
Parasympathetic innervation
(secretomotor)
Greater Petrosal Nerve (CN VII)
Nerve of the pterygoid canal
Pterygopalatine ganglion
Parasympathetic innervation
(secretomotor)
Which two para nerves use the
Submandibular ganglion?
Parasympathetic innervation
(secretomotor)
Chorda Tympani (CN VII)
Lingual nerve (CN V3) Submandibular ganglion
What is the parasympathetic pathway superior to the orbital fissure (name 3 pre-nerves, ganglion, and 1 post-nerve)?
preganglionic - facial nerve (CN VII), greater petrosal nerve, nerve of the pterygoid canal
synapse in the pterygopalatine ganglion.
postganlionic fibers distributed with the branches of the maxillary nerve - V2.
What is the pathway of sympathetic nerves that pass through the pterygopalatine ganglion (name four nerves that pass through)?
Postganglionic sympathetic vasomotor innervation:
arrives from the superior cervical ganglion via the internal carotid nerve, internal carotid plexus, deep petrosal nerve, nerve of the pterygoid canal and passes through the pterygopalatine ganglion to distributed with the branches of the maxillary nerve - V2
What is the parasympathetic pathway inferior to the orbital fissure (name 2 pre-nerve, ganglion, and 1 post-nerve)?
preganglionic - facial nerve (CN VII), chorda tympani, lingual nerve - V3
synapse in the submandibular ganglion
postganglionic fibers distributed with the lingual branches of the mandibular nerve - V3
What is the pathway of sympathetic nerves that pass through the submandibular ganglion (what two arteries does it follow before the submandibular ganglion)?
Postganglionic sympathetic vasomotor innervation:
arrives from the superior cervical ganglion via a plexus on the external carotid and facial arteries and passes directly through the submandibular ganglion to be distributed with the lingual branch of the mandibular nerve - V3.
The dorsum of the tongue has a median sulcus that divides it into lateral halves.
This terminates posteriorly in a pit, the foramen cecum, (embryologic origin of the thyroglossal duct).
From the foramen cecum, a V-shaped groove, the sulcus terminalis, radiates obliquely anterior toward the palatoglossal arch at the periphery of the tongue.
The dorsum of the tongue has a median sulcus that divides it into lateral halves.
This terminates posteriorly in a pit, the foramen cecum, (embryologic origin of the thyroglossal duct).
From the foramen cecum, a V-shaped groove, the sulcus terminalis, radiates obliquely anterior toward the palatoglossal arch at the periphery of the tongue.
What separates the anterior two thirds of the tongue from the posterior third of the tongue?
It is the sulcus terminalis which separates:
anterior two-thirds (oral portion) of the tongue (apex & body)
from the
posterior one-third (pharyngeal portion) of the tongue (root)
What are the characteristics of the posterior third of the tongue?
forms the anterior wall the oropharynx.
is devoid of papillae but imbued with submucosal lymphoid follicles collectively known as the lingual tonsil
mucosa of the tongue is reflected onto the epiglottis as the:
median and lateral glossoepiglottic folds and the intervening valleculae.
Which three of the four types of lingual papillae have taste buds? Which does not?
fungiform
Foliate
vallate
filiform papillae do not.
There are 8 muscles which manipulate the tongue
all 8 muscles are innervated by the ____ nerve? Except the palatoglossus muscle which is innervated by ____? which can also be considered to be a muscle of the soft palate
all 8 muscles are innervated by the hypoglossal nerve (CN XII) except the palatoglossus (CN X) which can also be considered to be a muscle of the soft palate