Anatomy & Histology of Oral Cavity, salivary, soft palate Flashcards
1
Q
Where is the oral cavity derived from?
A
The stomodeum
2
Q
What facilitates the formation of manageable food & what is it called?
A
Secretions from the salivary glands facilitate the formation of manageable food into bolus which can be swallowed.
3
Q
_ and _ facilitate the formation of bolus.
A
Teeth and saliva
4
Q
What is the extent of oral cavity?
A
from the lips to oropharygeal isthmus
5
Q
What muscle surrounds the oral fissure (lips)?
A
Orbiculris oris
6
Q
What is the motor supply of the skin around lips?
A
Facial nerve
7
Q
What is the sensory supply of the skin around lips?
A
upper lip maxillary and lower lip is mandibular
8
Q
What is the boundaries of the oral cavity?
A
Oral vestibule which is the slit like space between the lips and cheeks (superficially) and teeth & gingivae (deeply). And oral cavity proper the space posterior and medial to upper and lower dental arches
9
Q
What opens up in the oral vestibule?
A
Parotid gland
10
Q
What is the muscle that makes up the lateral wall (cheeks) of the oral vestibule?
A
Buccinator muscle
11
Q
What forms the roof of the oral cavity proper?
A
The hard and soft palates. They lie superiorly to the oral cavity proper
12
Q
What is the content of the oral cavity proper?
A
the tongue
13
Q
What does palate separate and what are the parts?
A
The soft and hard palate separates the oral cavity from the nasal cavity
14
Q
How is hard palate formed?
A
Hard palate is formed from the fusion of the palatine processes of the maxilla and the horizontal plates of the palatine bones
15
Q
How is soft palate formed?
A
palatine aponeurosis covered by mucosa. made of only tendons
16
Q
What does the palatine tonsils lie between?
A
Palatoglossal (anteriorly) and palatopharyngeal arches (posteriorly)
17
Q
What are the muscles of the soft palate?
A
Tensor veli palatine tenses soft palate and opens mouth during swallowing/ yawning, levator veli palatini elevates soft palate during swallowing/ yawning, palatoglossus elevates posterior part of the tongue, palatopharyngeus tenses soft palate, and musculus uvulae shortens uvula.
18
Q
What are the muscles of the soft palate supplied by?
A
All are supplied by CN X (vagus nerve) except tensor pilli muscle which is supplied by CN V3 (medial pterygoid)
19
Q
What pharyngeal arches contributes to the formation of head, neck and face?
A
1st pharyngeal arch, face: mesoderm differentiation, neural crest cells: bones and cartilage.
20
Q
What is the arterial supply of the palatines?
A
Comes from the descending palatine of maxillary artery (lesser and greater palatine artery) and ascending palatine artery (facial)
21
Q
What is the sensory nerve supply of hard and soft palate?
A
hard- greater palatine nerve and soft- lesser palatine nerve (CN V2)
22
Q
What is gag reflex?
A
when the posterior tongue/ mouth is touched, one gags. Afferent limb CN IX (glossopharyngeal nerve) and efferent limb CNX (vagus)
-if pharyngeal plexus is injured, the soft palate (uvula) deviates to the opposite side
23
Q
What are the parts of the tongue?
A
Root (posterior 1/3 and has lingual fossa), body (anterior 2/3), inferior surface, dorsum, and apex (tip of the tongue).
24
Q
What are the parts of the tongue?
A
Root (posterior 1/3), body (anterior 2/3), apex (tip of the tongue), dorsum of the tongue, and inferior surface.
25
What is the terminal sulcus?
V shaped sulcus on the dorsal surface
26
What is at the apex of the groove?
Foramen cecum which is the proximal part of the thyroglossal duct that forms the thyroid gland.
27
What are the types of papillae?
Vallate (largest at the front), foliate (occupies the side, vertical slits), filiform (occupies maximum area), fungiform (beaded like papillae, sometimes bright red appearance)
28
What are the significance of the papillae?
Filiform has no taste bud and foliate present as a child, around 2 years old only.
29
What connects the inferior surface of the tongue to the floor of the mouth?
Lingual frenulum
30
What are the extrinsic muscles of the tongue and what do they do?
Genioglossus, palatoglossius, styloglossus, and hyoglossus. Help with movement of the tongue
31
What are the intrinsic muscles of the tongue and what do they do?
Superior and Inferior longitudinal (curls tongue upward and downward), transverse ( narrows and longates) and vertical (flattens and broadens tongue). They change the shape of the tongue.
32
What are the motor innervation of the tongue?
All muscles supplied by Hypoglossal nerve except palatoglossal which is supplied by CN X (vagus nerve)
33
What is the anterior 2/3 general sensation of the tongue?
Supplied by Lingual nerve of trigeminal branch (CN V3)
34
What is the anterior 2/3 tase sensation of the tongue?
Chorda tympani of the CN XII branch (facial)
35
What is the posterior 1/3 of tongue supplied by?
Both general and taste sensation is supplied by glossopharyngeal (CN IX)
36
What nerve is damaged when tongue deviates to the paralyzed side?
injury to hypoglossal. Hypoglossal nerve paralysis
37
What drains the posterior 1/3 of the tongue?
superior deep cervical nodes
38
What drains medial part of anterior 2/3?
inferior deep cervical node
39
What drains the lateral parts of anterior 2/3?
submandibular nodes
40
What drains the apex and frenulum?
submental nodes
41
What are the salivary glands?
Parotid gland, submandibular, and sublingal
42
Where is the parotid gland located?
Between the mandible, styloid process and mastoid process. Its on both sides of the face in front of the tmj joint.
43
What is parotid sheath?
Found in the parotid gland, it is derived from the investing layer of the deep cervical fascia. It makes any infections more painful.
44
What are the structures found within the parotid gland?
facial nerve, retromandibular vein, and external carotid artery
45
What is the secretomotor supply of parotid gland?
auricolotemporal nerve
46
What is submandibular gland?
It lies on the floor of the mouth, below the mandible.Lies along the body of the mandible. Secretions from this are mixed type.
47
What does the submandibular supply?
Sublingual and submandibular glands
48
Where is sublingual found?
below the tongue. Lies on the floor of the mouth between the genioglossus and mandible
49
What secretions does sublingual produce?
Mucus like secretions
50
What is parotiditis?
Inflammation of the parotid gland, can occur in mumps, severe pain can occur in parotid sheath.
51
What should be id'ed and preserved during parotidectomy?
Facial nerve
52
What nerve supplies the face with their structures and branches of sensory supplied?
Motor supply is facial nerve (temporal, zygomatic, buccal, mandibular, and cervical) and sensory supplied by trigeminal nerve (opthalmic, maxillary and mandibular)
53
What is the structure of temporo-mandibular joint?
synovial bi-condoylar joint, above mandibular fossa of temporal bone and below head of mandible covered by fibrocartilage.
54
What elevates (open) mouth?
temporalis, masseter and medial pterygoids
55
What depresses and closes mouth?
lateral oterygoid
56
What protrudes the chin?
lateral pterygoid, masseter and medial pterygoids
57
What retrudes chin?
temporalis and masseter
58
What moves the mouth laterally, for chewing and grinding?
temporalis of the same side, ptergoids of opposite side, and masseter
59
What is the extent of the pharynx?
From the base of the cranium to the cricoid cartilage (C6 vertebrae)
60
What are the subdivisions of the pharynx and where are they found?
Nasopharynx (behind the nose), Oropharynx (behind the mouth), and Laryngopharynx (behind the larynx).
61
Oropharynx?
bounded by soft palate, base of tongue, palatoglossal and pharyngeal arches. Palatine tonsils are present in tonsillar sinus and it has digestive functions
62
Whatis the extent of the laryngopharynx?
From the epiglottis to the cricoid cartilage
63
Laryngopharynx?
Is continuous with the esophagus and communicates anteriorly with the larynx
64
What is piriform fossa?
A small depression of laryngopharyngeal cavity on each side of inlet.Branches of internal and recurrent laryngeal nerves lie deep to piriform fossa.
65
What are the motor nerve supply of the pharynx?
Motor nerve supple is CN X (Vagus nerve) except for stylopharyngeus which is CN IX (glossopharyngeal nerve)
66
What is the sensory nerve supply of the pharynx?
CN IX (glossopharyngeal nerve). Anterior and superior nasopharynx is supplied by maxillary nerve of trigimenal
67
What is pharyngeal tonsillar ring of Waldeyer?
It consists of lingual tonsil, palatine tonsils, tubal tonsils, and pharyngeal tonsils
68
During tonsillectomy, injury to what vein causes bleeding?
External palatine vein which drains into facial vein
69
What is the extent of the esophagus?
the esophagus is a fibromuscular tube that extends from the pharynx to the stomach.
70
Where does the esophagus pass through?
Passes through the esophageal hiatus of the diaphragm at T10 vertebrae
71
Where does the esophagus terminate at?
Terminates at esophagogastric junction by entering the cardial orifices of the stomach
72
What parts of the esophagus contains skeletal and smooth muscles?
Upper 1/3 has skeletal
Middle 1/3 has both
Lower 1/3 has smooth
73
What are the parts of the esophagus?
Cervical, thoracic and abdominal
74
Where is the cervical part of the esophagus located?
in the midline between the trachea and the cervical vertebrae and left side is thoracic duct
75
Where is the thoracic part?
Thoracic duct lies between two plueral cavities. The space is called mediastinum
76
What is located in front of the esophagus in the upper mediatinum?
trachea
77
What is located in front of the esophagus in the lower part of the mediastinum?
left atrium (NB- enlargement of left atrium manifests as dysphagia)
78
What are the contrictions of the esophagus?
cervical, thoracic and diaphragmatic
79
What is the cervical controstrictions?
caused by cricopharyngeus muscle. 15 cm from incisor teeth is where it is found
80
What structures do the thoracic constrict?
it crosses the aorta and the left main bronchus
81
What is diaphragmatic constriction?
passes through the esophageal hiatus of diaphragm (40cm)
82
What is tracheo-esophageal fistula?
most common birth defect of the esophagus. Result from failure in partitioning of esophagus and trachea. In most common type of TEF, upper esophagus ends in a blind pouch and lower part communicates with the trachea
83
Lower end of esophagus is a site for portosystemic shunt. What is this?
When abdominal part drains into portal venous sytem, thoracic part drains into systemic venous circulation. When dilated, these veins can form esophageal varices which cause vomitting of blood.
84
What is esophagael cancer?
It causes dysphagia (difficulty swallowing). Compresses recurrent laryngeal nerves and produces hoarseness.
85
What makes up the oral cavity?
Lips, cheeks, gums, teeth, tongue, uvula and palate
86
What lines the oral cavity?
oral mucosa which is made up of epithelium and connective tissue. It is divided into 3 parts depending on location
87
Where is masticatory mucosa and what does it contain?
Gingiva and hard palate. Contains stratified squamos keratinized/ parakeratinized epithelium.
88
Where is specialized mucosa and what does it contain?
On the dorsal surface of the tongue and it contains papillae
89
Where is lining mucosa and what does it contain?
Remaining part of the cavity and contains nonkeratinized stratified squamos
90
What are the regions of the lip?
Cutaneous (covered by thin skin, has hair follicles and sebaceous and sweat glands)
Vermilion region (lined by stratified squamos supported by connective tissue containing blood vessels that gives it the red color. No glands are present in the mucosa of this region, dries out during cold weather and gets cracked)
Oral mucosa (wet surface- mucous salivary glands)
91
What are the anterior 2/3 of the tongue composed of?
Skeletal muscle in three directions: longitudinal, oblique, and transverse
92
What is the posterior 1/3 of the tongue composed of?
It displays the lingual tonsils (aggregations of lymphocytes)
93
The dorsal surface of the tongue contains?
Specialized mucosa with taste buds, lingual papillae, and lingual tonsils
94
The ventral surface of the tongue contains?
Lining mucosa with three pairs of minor salivary glands
95
Filiform papillae
are the most abundant, conical in shape, have no taste buds and contains stratified squamos keratinized epithelium
96
Fungiform papillae
tend to be more numerous near the tip of the tongue. Has non keratinized stratified squamos epithelium. Appear bright red due to blood vessels. Possess a few taste buds on their free surface.
97
Foliate papillae
are located posterolateral of the anterior 2/3 of tongue. Present as shallow furrows that possess taste buds for the first 2 years then disappear.Glands of Von Ebner release their secretions into the furrow
98
Circumvallate papillae
largest papillae, located anterior to terminal sulcus, possess numerous taste buds and are surrounded by deep, moat like furrow. Glands of von Ebner release seros secretions into bottom of moat-like depression.
99
What is taste buds?
Oval, pale staining bodies that extend through the thickness of the epithelium
100
What is the small opening onto the epithelial surface of the apex of the taste bud called?
Taste pore
101
What are the three principle cell types found in taste buds?
- gustatory cells' microvilli project through taste pore and they synanpse with afferent sensory axon
-supporting cells
-basal cells: stem cells for the two other cell types
102
What is salivon?
Basic secretory unit of any salivary gland and consists of the acinus, intercalated duct, and excretory duct.
103
What are acini and what do they contain?
Spherical, containing serous cells and mucous, or mixed with both. Myoepithelial cells are present at the base of secretory cells.
104
Difference between serous and mucous cells?
Serous are protein secreting, circular, round nucleus, has small lumen
Mucous cells are mucin secreting cells with larger lumen and has flat nucleus towards base and columnar
105
How is secretions from acinus drained?
Drained by intercalated duct (lined by simple cuboidal), which merges into striated duct and finally into the excretory duct (stratified cuboidal/columnar), which is surrounded by connective tissue.
106
What is the structure of the cells of the striated ducts?
Has numerous basal membrane infoldings that contain mitochondria, giving them striated appearance.
107
Histology of parotid gland
only contain serous acini with adipose tissue distributed
108
Histology of submandibular gland
contains predominantly serous but also mucous/mixed acini (with visible demilunes), striated are evident
109
Histology of sublingual gland
are mixed but primarily contains elongated mucous acini. Serous component visible as a demilunes
110
What are the layers of the alimentary canal?
Mucosa, submucosa, muscularis propia and serosa or adventitia
111
The mucosa/ mucous membrane consists of?
The epithelial, the lamina propia (loose connective tissue rich in blood vessels, lymphatics, lymphocytes, smooth muscle cells, and often small glands), and muscularis mucosae (thin layer of smooth muscles separating mucosa from submucosa).
112
What is found in the submucosa?
Connective tissue with larger lymph vessels and submucosal (Meissner) plexus of autonomic nerves. May also contain glands and significant lymphoid tissue.
113
What is found in the musculosa?
Consists of two layers of smooth muscles. First internal layer contains circular fibers and external layer contains longitudinal fibers. Connective tissue between the layers contain blood vessels, lymph and myentric (aurbach) plexus which generate and coordinate contractions.
114
What is found in serosa and adventitia?
adventitia - thin sheet of loose connective tissue, rich in blood vessels, lymphatics, and adipose.
serosa- similiar to adventitia, but covered with simple squamos (mesothelium)
115
What happens if the nerve plexuses in the GI are absent/damaged?
Disturbance in the motility and dilations in some areas of GIT.
In Hirschsprung disease, plexus in DT enteric NS are absent or severly injured (problem with neural cell migration)
116
The four layers of the GI tract are:
The mucosa has non keratinized stratified squamous epithelium.
The submucosa contains small mucus-secreting glands, the esophageal glands which lubricated and protect the mucosa
Muscularis externa: inner circular, outer longitudinal. Upper striated, middle mixed and lower smooth
Adventitia forms the most outer layer except within the abdominal cavity where it is serosa.
117
What happens at the esophagogastric junction?
Non keratinized stratified squamor changes abruptly to simple columnar. Also contains eosophageal glands that secrete additional neutral mucus to protect the esophagus from regurgitated gastric contents.
