Oral Cavity Histology Week 1 Flashcards
Heinrich Waldeyer first described embryological, anatomical and functional studies about _________ and also named the chromosome
naso-oropharyngeal lymphatic tissue
True/False: The lumen of the GI tract is physically and functionally external to the body
True
True/False: The alimentary canal mucosa is the surface across which most substances enter the body
TRUE
Describe the two parts of the oral cavity
1) Oral cavity proper - opening between teeth
incl tongue, major and minor salivary glands, tonsils
2) vestibule = the area in between the teeth and cheeks
Describe the three types of mucosa associated with the oral cavity and where they are located
1) Masticatory mucosa
2) Lining mucosa
3) Specialized (gustatory) mucosa
The masticatory mucosa is found in the gingiva and hard palate.
The lining mucosa is found everywhere else except the tongue.
The specialized mucosa is on the tongue.
What type of epithelia are found on the mucosa associated with the oral cavity? Any special structural features?
The masticatory and lining mucosae containing stratified squamous epithelium.
Both have parakeratinized type, masticatory mucosa also has keratinized type. Lining mucosa does not have keratinized type.
The specialized mucosa (gustatory) contain papillae and taste buds on its dorsal surface.
What two types of epithelium are found on the lip and where?
Stratified squamous on skin of lip
Parakeratinized stratified squamous on outside of lip (vermillion) [hair follicles are on vermillion]
Where on the lip are labial glands found?
inside
What makes up the core of the lip?
skeletal muscle - called orticularis oris
What are the two types of teeth? How many of each are present?
deciduous (baby) - 20
permanent - 32
What are the three components of the tooth and where are they found?
Enamel, dentin, cementum
enamel is outermost, and dentin is just deep to enamel
The three components of the tooth are produced by different cells with different embryological origins. Describe.
Enamel is produced by ameloblasts, derived from the ectoderm.
Dentin is produced by odontoblasts, derived from neural crest cells.
Cementum produced by cementoblasts
What are the three sections of the tooth? Describe their components.
1) Crown
2) Neck
3) Root
All three components contain dentin.
The crown and neck contain enamel.
The neck and root contain gingival epithelium.
The crown contains dentinal tubules, whereas the root contains the pulp chamber [nerves and vessels] and cementum.
What happens when gingival epithelium recedes?
dentin is exposed, acts like a sieve, liquids can flow right in and hit nerves
The tongue is divided into dorsal and ventral surfaces. Describe what is commonly found on the dorsal surface. [basics]
On the anterior 2/3 of the dorsal tongue, there are four types of lingual papillae
On the posterior 1/3, it contains a lingual tonsil which is part of Waldeyer’s ring
On the anterior 2/3 of the dorsal surface of the tongue, there are four types of lingual papillae. Describe each.
1) Circumvallate papillae
2) Foliate papillae
3) Fungiform papillae
4) Filiform papillae
The circumvate are in front of the V-shaped sulcus terminalis.
The fungiform are on the marigin of the tongue and the filiform are on the surface.
Foliate are not abundant and seen primarily in newborns.
All contain taste buds except the filiform papillae.
The filliform papillae increase friction between the tongue and food (think cats).
The circumvate papillae are associated with Ebner’s glands.
Describe the features on the ventral surface of the tongue
The ventral surface contains the lingual frenulum.
The deep lingual veins can be seen on both sides of the frenulum, allows sublingual admin of drugs
In addition to the three papillae of the dorsal tongue, taste buds are also found in which three regions?
oral pharynx
soft palate
posterior surface of epiglottis
What are the three types of cells that make up taste buds?
neuroepithelial sensory cells
supporting cells
basal cells
