Histology of oral cavity, tooth, pharynx and oesophagus Flashcards
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Name the types of epithelium in the oral cavity and which structures they line
- Keratinized stratified squamous epithelium- gum, hard palate.
- Nonkeratinized stratified squamous epithelium- soft palate, cheeks, floor of mouth, pharynx.
Name the 3 different covered surfaces of the lips
- Internal mucous surface
- Red vermillion zone (Transitional zone)
- Outer surface
Which covered surface of the lips does not have any salivary or sweat glands?
Red vermillion zone aka Transitional zone
What kind of epithelium lines the internal mucous surface?
Thick nonkeratinized epithelium
What type of epithelium lines the Transitional zone?
Thin keratinized stratified squamous epithelium
What separates the anterior 2/3 from the posterior 1/3 of the tongue?
Sulcus Terminalis (V-shaped)
Which surface of the tongue contains papillae and massed lingual tonsils
Dorsal surface
What takes up 1/3 of the tongue posteriorly
Massed lingual tonsils
Skeletal muscles of the tongue are oriented in the same direction. True of False
False; they are oriented in all directions
Name the 4 types of lingual papillae and the order of which they appear on the tongue
- Filiform papillae
- Fungiform papillae
- Foliate papillae
- Vallate (circumvallate) papillae
Which structures are formed between vallate papillae
Von Ebner Glands- provides continuous flow of fluid over taste buds
Which type of lingual papillae is conical shaped, heavily keratinized and has a gray appearance to the surface?
Filiform papillae
Which is the largest papillae and state its size
Vallate papillae; diameters 1 to 3mm
Which papillae does not have any taste buds in them
Filiform papillae
How many cells are in taste buds and what is there lifespan
50 to 100; 7 to 10 days
Which nerve carries the taste of the anterior 2/3 of the tongue
Facial Nerve (CN 7)
Which nerve carries the taste of the posterior 1/3 of the tongue
Glossopharyngeal nerve (CN 9)
There are 32 permanent teeth in adults. True or False?
True
20 of the permanent teeth are preceded by primary teeth true or false?
True
How many teeth are in a quadrant ?
Eight teeth: 2 incisors, 1 canine, 2 premolars, 3 molars
Another name for primary teeth
Deciduous or milk teeth
What type of tissue is present in the pulp cavity
mesenchymal connective tissue
Where does the blood vessels enter the tooth from?
Apical foramina at root tips
What type of ligaments hold the tooth to the bone of the jaw
Periodontal ligaments
What makes up 70% of dentin
Hydroxyapatite
Which cells produces dentin and lines the pulp cavity
Odontoblast
When does predentin mineralize to become dentin
Within 1 day
Where is predentin secreted from
Odontoblast
Odontoblast is derived from neural crest in mesenchyme of developing pulp cavity. True or False?
True
The enamel is the hardest component of the human body. True of False?
True
How much percent of calcium hydroxyapatite is present in the enamel
96%
Name the cell that produces enamel
Ameloblasts
What is the main structural protein of the developing enamel
Amelogenin
Ameloblasts are derived from
Ectodermal lining of embryonic oral cavity
When does the primary teeth begin to erupt
6 months after birth
What is the ‘bell stage’
When the development of secondary tooth arrest until 6 years of age
Where does tooth formation begin
Embryo
What induces ameloblasts to begin secretion of an enamel rod
contact with dentin
What is the Periodontium comprised of?
Cementum, Periodontal ligament and Alveolar bones
Cementum is avascular; True of False
True
What type of epithelium is the oral pharynx lined by?
Stratified squamous nonkeratinized epithelium
What are tonsillar crypts?
Deep grooves that invaginate each tonsil
Which type of tonsil lacks crypts and is a part of MALT?
Pharyngeal tonsil
How long is the oesophagus of adults?
25cm
What type of epithelial cells lines the mucosa of the oesophagus
Nonkeratinized stratified squamous epithelium
Name the four layers of the oesophagus and the connective tissue associated with each
Mucosa- Thin layer pf connective tissue
Submucosa- Dense irregular connective tissue
Muscularis externa- none
Adventitia- Loose connective tissue
Difference between the upper and lower muscularis externa of the oesophagus
Upper oesophagus- muscularis externa: inner circular muscle layer and outer longitudinal muscle layers composed of skeletal muscle fibers.
Lower oesophagus- composed of smooth muscle fibers instead
