Oral Cavity Flashcards
What is the oral cavity bound by anteriorly, laterally, posteriorly, superiorly, and inferiorly?
anteriorly by the lips, laterally by the cheeks, posteriorly by the palatoglossal arches, superiorly by the hard & soft palates, and inferiorly by the mylohyoid m.
What is the oral cavity proper?
the area internal to the dental arches
What is the oral vestibule?
the area outside the dental arches. narrow space between the labii & cheeks and the teeth
How does the oral vestibule communicate with the external environment? when does it become continuous with the oral cavity proper?
via the oral cavity. It becomes continuous with the oral cavity proper posterior to the third molars
What is contained within the oral vestibule?
buccal surfaces of the teeth, alveolar processes, and associated gingivae, papillae & openings of the parotid (Stensen’s) ducts, openings of numerous minor salivary glands, frenulum of upper lip, and frenulum of lower lip.
The oral cavity proper is continuous with the _________________ via the ___________________
oropharynx : oropharyngeal isthmus, the space between the palatoglossal arches
What is contained within the oral cavity proper? (not including the sublingual space)
lingual surfaces of teeth, alveolar processes, and associated gingivae, tongue (body), lingual frenulum sublingual caruncles & openings of the submandibular (Wharton’s) ducts, sublingual folds & openings of the sublingual ducts, and openings of numerous minor salivary glands.
What is the sublingual space?
the area between the mucosa of the floor of the oral cavity proper and the mylohyoid m.
What is the sublingual space continuous with posterior to the mylohyoid m.?
the submandibular fascial space (inferiorly) and lateral pharyngeal fascial space (posteriorly)
What is the sublingual space continuous with posterior to the mylohyoid m.?
the submandibular fascial space (inferiorly) and lateral pharyngeal fascial space (posteriorly)
What may happen to infections in the sublingual space?
They may spread to adjacent spaces (submandibular, lateral pharyngeal, retropharyngeal, and beyond)
What is ludwig’s angina? How serious is it?
Cellulitis in the sublingual, submandibular, and sometimes submental space that ends up endangering the airway and requiring immediate attention. It is life threatening.
What is contained within the sublingual space?
sublingual glands (and associated ducts), submandibular ducts, lingual aa. (and brs.), lingual vv. (and tributaries), lingual nn. (and associated submandibular ganglia) hypoglossal nn. (and vena comitantes), and the deep lobe of submandibular gland.
What is the smallest of the three main salivary glands? what are they?
the sublingual gland is the smallest. They include the parotid, submandibular, and sublingual glands
Where is the sublingual gland? When does it become referred to as the “sublingual fold”?
It is located superior to the mylohyoid m. and when covered with mucosa, it forms the sublingual fold
How do the sublingual glands drain?
via numerous small ducts along the sublingual folds
What else is located in the area of the sublingual fold?
The deep, smaller part of the submandibular gland is in this area, closely associated with the posterior end of the sublingual gland.
How is the mylohyoid line formed?
by the attachment of the mylohyoid muscle to the mandible
What two glands are associated with the mylohyoid line?
sublingual gland superior, and submandibular gland inferior
What branch of the external carotid is the lingual a.?
the second branch, typically located anteriorly
What structures does the lingual a. pass through?
between the hyoglossus m. and the middle pharyngeal constrictor m.
What does the lingual a. supply?
the floor of the oral cavity, and the tongue.
What are the chief branches of the lingual a.?
Dorsal lingual brs., Sublingual a., Deep lingual a.
Where do the dorsal lingual brs. arise? What do they supply?
the dorsal lingual brs. arise medially of the hyoglossus m. and supply the posterior tongue, soft palate, and palatine tonsil
Where does the sublingual a. arise? What does it supply?
the sublingual a. arises anteriorly to the hyoglussus m. and supplies the sublingual gland, and muscles and tissues of the floor of the oral cavity.
Where does the deep lingual a. arise? what dies it supply?
the deep lingual a. (terminal branch of the lingual a.) lies along the inferior margin of the tip of the tongue and supplies the anterior tongue.
What do nearly all branches of the lingual artery do along the midline?
anastomose with their contralateral paired artery.
What does the lingual n. cross with deep to the mucosa of the oral cavity proper? Where does it pass?
the submandibular duct. They pass roughly midway through the oral cavity
What does the lingual n. innervate? how does it get there?
The lingual nerve leaves the mandibular n. (V3) of the trigeminal and dives deep to the submandibular duct, the ascends to the anterior base of the tongue where it provides sensory innervation to the anterior 2/3 of the tongue and the floor of the oral cavity
What space does the submandibular duct (Wharton’s) traverse?
the space between the submandibular gland and the sublingual caruncle
Describe the location of the submandibular duct.
The duct is located between the hypoglossal n. and lingual n. in association with the hyoglossus m.
What space does the lingual nerve traverse?
the infratemporal fossa.
Where is the lingual n. in association with the inferior alveolar n.?
It runs medially of the inferior alveolar n.
What nerve joins with the lingual n. just after it branches off of the mandibular n. (V3)? What is its purpose?
the chorda tympani joins with the lingual n. It carries presynaptic parasympathetic fibers from the facial n. to the submandibular gland, and provides taste to the body of the tongue.
Where does the lingual n. enter the oral cavity?
superior to the mylohyoid m.
Where is the submandibular ganglion?
submandibular ganglion is delicately associated with the lingual n. and is superior to the deep portion of the submandibular gland
What are the four named peripheral parasympathetic ganglia?
ciliary, pterygopalatine, submandibular, and otic ganglion
Where does the submandibular ganglion receive preganglionic parasympathetic fibers from?
the submandibular ganglion receives preganglionic parasympathetic fibers from the chorda tympani, a branch of the facial n
After synapsing in the submandibular ganglion, postganglionic parasympathetic fibers leave the ganglion to… by means of…
innervate the submandibular and sublingual glands, among other smaller glands (e.g. anterior lingual) by means of the lingual n., a branch of V3.
What is a vena comitans?
it is an “accompanying vein”
What is the vena comitans of the hypoglossal n.? What does it do?
It is a tributary of the lingual v. It accompanies the hypoglossal n. (CNXII) inferiorly along the hypoglossus m.
When we say “cheeks” what is included?
the skin, buccinator m., and mucosa
What are the cheeks innervated by?
the long buccal nn. (of V3)
Generally speaking, what nerve innervates the teeth?
the alveolar nn.
What nerve innervates the mandibular teeth?
the inferior alveolar n. of the mandibular n. V3
What nerves innervate the maxillary teeth?
the superior alveolar nn. of the maxillary n. V2
What composes the superior dental plexus?
The posterior superior alveolar brs., middle superior alveolar brs., and anterior superior alveolar brs.
Where do the posterior superior alveolar (PSA) brs. come from, and what do they serve? How do they get there?
the posterior superior alveolar brs. are a direct branch of V2 in the pterygopalatine fossa and afferently serve the maxillary molars. The branches descend deep (not through) to the mucosa of the maxillary sinus
Where do the middle superior alveolar (MSA) brs. come from, what do they serve?
The middle superior alveolar brs. are frequently absent. They branch off of the infra-orbital n (V2) and afferently serve portions of the maxillary sinus, and the maxillary premolars (sometime M1).
Where do the anterior superior alveolar (ASA) brs. come from and what do they serve?
the anterior superior alveolar brs. branch off of the infra-orbital n. and afferently serve the maxillary canines and incisors.
What nerves innervate the gingivae of your maxillary anterior teeth? P1, P2, M1, M2, M3?
V2>pterygopalatine ganglion>Nasopalatine n. - V2>pterygopalatine ganglion>Greater palatine n.
Maxillary teeth innervations: Anterior, P1/P2, M1/M2/M3
Anterior: ASA brs. - P1/P2(sometime M1): MSA brs. - M1/M2/M3: PSA brs.
Maxillary buccal gingiva innervation: Anterior, P1/2, M1/2/3
Anterior: infra-orbital n./ASA brs. - P1/2: Infra-orbital n./MSA brs. - M1/2/3: PSA brs.
What nerve innervates the mandibular lingual gingiva?
the lingual n. (V3)
Mandibular teeth innervations:
Incisive brs. of IAN: Anterior/P1 Dental brs. of IAN: P1/2 M1/2/3
Mandibular buccal innervations:
Anterior/P1/P2: Mental bra. of IAN - M1/2/3: (long) buccal n.
What are the intrinsic muscles of the tongue?
superior longitudinal, inferior longitudinal, transverse, and vertical.
What are the actions of the intrinsic muscles of the tongue? What are they innervated by?
Intrinsic tongue muscles independently (and in unison) alter tongue shape and perform smaller, more precise movements. Intrinsic tongue mm. are innervated by the hypoglossal n. (CN XII).
What nerve innervates the extrinsic muscles of the tongue?
hypoglossal n. (except palatoglossus - Vagus)
Genioglossus m. origin, insertion, innervation, action:
Superior mental/genial spines : Tongue : Hypoglossal : Bilateral contraction: depress and protrude tongue Unilateral contraction: deviate to the contralateral side
Styloglossus m. origin, insertion, innervation, action:
Styloid process of temporal bone : posterolateral tongue : hypoglossal : Retracts and elevates tongue
Hyoglossus m. origin, insertion, innervation, action:
Greater horn of hyoid bone : tongue : hypoglossal : Retracts the tongue & depresses the ipsilateral side of tongue
Palatoglossal m. origin, insertion, innervation, action:
Palatine aponeurosis : lateral tongue : Vagus (pharyngeal plexus): Elevates and retracts tongue; closes the oropharyngeal isthmus during deglutition (swallowing)
What does the terminal sulcus divide the tongue in to?
the body (persulcal/oral part) and root (postsulcal/pharyngeal part)
Describe the path of the median sulcus
The median sulcus runs superficial to the fibrous septum (whole length of tongue) and converges with the terminal sulcus.
Where do the three sulci of the tongue converge?
the foramen caecum
What is the foramen caecum?
the convergence of the 3 sulci of the tongue. It is an embryonic remnant of the thyroid diverticulum and thyroglossal duct.
What shape do the three sulci form?
an arrow pointing toward the epiglottis
What runs just anterior to the terminal sulcus?
two rows of vallate papilla running parallel to their sides terminal sulcus
Where do the terminal sulci run to laterally?
the palatoglossal arch
Where do the body and root of the tongue lie?
Body is within the oral cavity proper, the root is within the oropharynx
What is included within the root of the tongue?
the root of the tongue extends from the terminal sulci (and their respective palatoglossal arch) posteriorly to the epiglottic valleculae where it is attached to the epiglottis via the median, and two lateral glossoepiglottic folds.
Are there papillae on the root of the tongue?
no
What are the lingual tonsils?
they are submucosal collection of lymphatic nodules that give the root of the tongue its rugosa appearance.
What connects the ventral part of the tongue to the floor of the oral cavity?
the lingual frenulum.
What is it called when an individual has a shortened and thickened lingual frenulum that may limit the mobility of the tongue?
ankyloglossia
Why would ablation of the lingual frenulum be necessary
if an individual has ankyloglossia. Less frequently to aid in speech, but it may help an infant with latching for breastfeeding.
What gives shape to the sublingual folds?
the the sublingual glands, and the ducts of the submandibular gland.
Where is the sublingual caruncle?
at the confluence of the sublingual glands and lingual frenulum
What is the sublingual caruncle?
it is where the submandibular ducts secrete saliva into the oral cavity
Where can the lingual veins be seen?
deep to the inferior (ventral) surface mucosa and between the lingual frenulum and fimbriated folds (which flank the lingual frenulum on the ventral surface of the tongue)
How is the tongue afferently innervated with respect to the vallate papilla?
Anterior to the vallate papilla: lingual n. (V3) - Posterior to the vallate papilla: glossopharyngeal n.
Where is there a slight overlap of somatic afferent innervation of the tongue? what nerves are involved?
the posteromedial root of the tongue : the glossopharyngeal n., and Vagus n. (via the internal root of superior laryngeal n.)
How is the tongue viscerally afferently innervated (taste) with respect to the vallate papilla?
Anterior to vallate papilla: facial n. (chorda tympani > lingual n.) - Posterior to vallate papilla: glossopharyngeal n.
What are the four types of lingual papillae?
filiform, fungiform, foliate, and vallate papillae
Describe the filiform papillae.
small, conical eruptions covering the dorsal anterior two-thirds of the tongue. Filiform papillae are not associated with taste buds, but rather are important for the tactile sensation and manipulation of food items.
Describe the fungiform papillae.
moderately sized, mushroom-shaped eruptions interspersed throughout the filiform papillae. Fungiform papillae host taste buds innervated by the axons from chorda tympani (facial n.) by way of the lingual n. (V3)
Describe the foliate papillae.
found in trenches on the lateral margins of the tongue. Taste buds associated with foliate papillae are in greatest density during childhood, and often diminish with age
Describe the vallate papillae.
“circumvallate papillae”: the largest of the lingual papillae. Vallate papillae host taste buds innervated by the axons from the glossopharyngeal n. (CN IX), even though they lie on the presulcal side of the tongue
Which extrinsic muscle of the tongue closes the oropharyngeal isthmus?
the palatoglossus m.
What is the “fauces” of the oral cavity?
it is where the oral cavity communicates with the oropharynx
What is “gingiva proper”?
gingiva firmly attached to the bone. “keratinized gingiva” - keratinized squamous epithelium
What is “alveolar mucosa”?
non-keratinized gingiva
How many “deciduous” teeth do you have? (baby teeth)
20
What teeth are considered succedaneous teeth?
teeth that follow deciduous teeth. If there was not a deciduous tooth in the place, the replacement tooth is not succedaneous
What happens to the pulp cavity as you age?
it gets smaller as the dentin takes up more and more space
What artery gives off the supplying arteries of the mandible and maxilla?
The Maxillary a. (of the external carotid a.)
What arteries supply the mandibular and maxillary teeth?
Maxillary: Anterior, Middle and Posterior Superior Alveolar aa. — Mandibular: Inferior Alveolar a.
What path does the inferior alveolar a. take to supply the mandibular teeth?
It is the first branch of the maxillary artery, and enters the mandible through the mandibular foramen where it then supplies the mandibular teeth, exiting the mandible via the mental foramen.
afferent (non special) innervations of the body/root of the tongue:
Special afferent innervation of the tongue (taste):
Geniohyoid origen, insertion, action:
What lymph nodes does the tip of the tongue drain to? middle tongue/posterior tongue?
tip of tongue drains to Submental lymph nodes. Middle/posterior tongue drains to deep cervical lymph nodes.
