Oral Cavity Histology Flashcards
- Physically and functionally external to the body
- Segments are specialized for **specific aspects of digestion and absorption
**
Allimentary Canal
- Tongue
- teeth
- salivary glands,
- pancreas
- liver
- gallbladder
Organs of the GI
Function of?
- digestive enzymes (pancrease)
- HCl(stomach)
- mucin, antibodies
Secretion of mucosa
Function of?
- vitamins
- water
- electrolytes
- bile component
- cholesterol
Absorbtion function of mucosa
function of
prevent entry of noxious substances, antigens, pathogens.
Barrier funcion of mucosa
first line of immune defense, innate.
Immunological protection of mucosa
What are the 2 primary spaces of the oral cavity?
- Vestibule
- Oral Cavity proper
space between lips, cheeks, and teeth
Vestibule
behind teeth, bounded by hard and soft palates, tongue and floor of the mouth, and entrance to oropharynx
Oral cavity proper
What are the 3 major paried salivary glands?
- Parotid
- Submandibular
- Sublingual
What are the minor salivary glands?
aggregations of lymphatic nodules
- Waldeyers tonsillar ring
(paletine, tubal, pharyngeal, lingual)
3 mucousa of the oral cavity?
- Masticatory
- Lining
- Specialized
Keratinized and Parakeratinized stratified squamous epithelium
Gingiva and hard palate
Masticatory mucosa
- Generally nonkeratinized, may be parakeratinized
- Lips, cheeks, alveolar mucosal surface, floor of mouth, inferior surfaces of the tongue, soft palate
- Covers striated muscle keep under tongue.
Lining mucosa
- Papillae Taste buds
- Dorsal surface of the tongue
- Generate chemical sensation of taste
Specialized mucosa
keratinized epithelium that has not lost its nucleus, nucleus remains until cell is exfoliated.
Parakeritinzied
thick papillary layer of loose connective tissue
* Contains blood vessels and nerves
Lamina Propria
3 layers of the lining mucosa
- Stratum superficiale (surface)
- Spinosum (middle), several layers thick
- Basale (bottom) single layer
The lining mucosa is highly ___
Higly vascularized!
good for oral transmucosal drug delivery
An advatage of high vasculairzation of the lining mucosa is what?
Drug enters directly into systemic circulation bypassing the liver (first pass), so lower doses still effective
Linning mucosa
- Sebaceous glands not associated with a hair follicle
- Lateral to the corner of the mouth and opposite the molar teeth
Fordyce Spots
- Salivary antimicrobial peptides
- β-defensins
- α-defensins
- Secretory immunoglobulin A
all do what?
Function as a protective barrier produced by oral mucosa. Maintain normal oral microbiome
Distruption with xerostomia or immmunocompise BAD
Muscular organ projecting into the oral cavity
Tongue
Lingual Muscles
one attachment outside of the tongue
Extrinsic muslce
Lingual Muscles
without external attachment
Intrinsic muscle
Lingual muscle
arranged in three planes (only muscle in body with this)
* allows flexibility for speech + bolus mvmt
Strated muscle of tongue
Dorsal surface of tonfue
Anterior-posterior separated by ____ right behind circumvale papillae
sulcus terminalis
apex of sulcus terminalis
Remanent from embryonic formation of thyroid gland
Foramen cecum
smallest and most numerous,does NOT contain taste buds
Filiform
mushroom-shaped, contains taste buds, more numerous near tongue tip
Fungiform
large, dome shaped (8-12), contain taste buds, von Ebner glands empty serous secretions at base
Cicumvallate
lateral edge of tongue, become less pronounced with age, contain taste buds
Foliate
?
Circumvalllate
Cells in taste buds
Most numerous cells in taste buds. Replaced about every 10 days. Sensory cells. Are connected with afferent.
neuroepithelial cells
Cells in taste buds
do not synapse with nerve cells, not connected with afferent nerve fibers.
Supporting cells
Cells in taste buds
stem cells for sensory and supporting cells
basal Cells
What sensation or receptor?
Sweet, salty, bitter, sour, umami
Chemical Sensation
What sensation or receptor?
Bitter, sweet, and umami
G-protien coupled taste receptors
What sensation or receptor?
Sour
Generated by H+ channel
What sensation or receptor?
Salty
Generated by Na+ channel
2 ____ produce a wide variety of protiens
2 taste receptor genes.
Tongue Nerve Supply
General sensation:
* ant 2/3?
Ant 2/3= CN5
gen sen
Tongue Nerve Supply
General sensation:
* post 1/3?
Post 1/3= CN9/CN10
gen sen
Tongue Nerve Supply
Taste:
* Ant 2/3?
Ant 2/3= chorda tympani branch of CN7
taste
Tongue Nerve Supply
Taste:
* Post 1/3?
Post 1/3= CN9/CN10
taste
Tongue Nerve Supply
Motor?
CN12 hypoglossal
Motor
hard, thin, translucent layer of acellular mineralized tissue that covers the crown of the tooth
Enamel
Hardest substance in body
deep to enamel in the crown and the cementum in the root
Dentin
thin, pale-yellowish layer of bone-like calcified tissue covering the dentin of the root of the teeth
Cementum
96-98% if enamel is made of what?
calcium hydroxyapatite
50% in bone
trend in enamel thickness?
Varies, up to 2.5mm on cusp of crowns, thinnest cervically.
Explain enamel arrangement
- Rods
- Parallel to long axis rod
In deciduous teeth a line of ____ represents **nutritional changes which take place between pre and post natal life.
**
Hypermineralization
mineralization (ex. Childhood illnesses, mothers diet during pregnancy) can affect the __ of teeth
mineralization in teeth.
enamel is produced by _____ process of ____
Ameloblast in process of amelogenisis
Stages of amelogenesis
formation of mineralized tissues followed by dentin formation
matix prodiction
Stages of amelogenesis
maturation of mineralized enamel matrix, removal of organic material
Matrix mineralization
removal of organic elements
Proteins of the developing enamel
establish and maintain the spacing of the enamel rods
Amelogenin
Proteins of the developing enamel
signaling proteins
Ameloblastins
Proteins of the developing enamel
proteins distributed throughout the enamel layer for arrangments
Enamelins
Proteins of the developing enamel
proteins of the dentinoenamel junction
Tuftelins
Cementum is produced by?
Cementoblasts
- Secrete an extracellular matrix called cementoid
- incorporated into the cementum and become cementocytes
Cementoblasts
collagen fibers which project from periodontal ligament into cementum
Sharpey Fibers
Calcified material that forms most of the tooth substance
Dentin
Dentin is secreted by?
Odontoblasts
- Newly secreted organic matrix, closest to odontoblasts
Predentin
initiates mineralization (helps convert pre dentin to dentin)
Dentin phosphoprotein
involved in mineralization of dentin
Dentin sialoprotein
- Loose connective tissue with rich vascularization and abundant nerve supply
- Blood Vessels and nerves enter via apical foramen
Dental Pulp
Nerve fiber enter inner portion of dental tubules and interact with odontoblast processes, how teeth recognized heat and cold via receptros.
Sensation of pain
increse substance P
thin layer of compact bone which forms the wall of the alveolus
* Attachment site of PDL
Alveolar bone proper
- Tooth fixation
- Tooth support
- Bone remodeling (during tooth movement)
- Proprioception
- Tooth eruption
PDL
Masicatory mucosa
Gingiva mucosa
Adhears to tooth
JE
lined with crevicular epithelium, continuous with junctional epithelium
Gingival sulcus
All tissues involved in the attachment of a tooth to the maxilla or mandible are a part of the periodontium
Periodontum
* Crevicular and junctional epithelium
* Cementum
* Periodontal ligament
* Alveolar bone
What are the 3 major salivary glands
- Parotid
- Submandibilar
- Sublingual
paired glands with long ducts that empty into the oral cavity
What are the 4 minor salivary glands
- Lingual
- Labial
- Buccal
- Molar
- palatine
located in the submucosa of the oral cavity
3 types of secratory gland acini>
- Serous
- Mucous
- Mixed
Only serous cells (parotid, serous secretory production only, watery)
Seorus acini
Only mucous cells
Mucous acini
Mixture of serous and mucous cells (submandibular & sublingual)
Mixed acini
Pyramidal cells
Large amounts of rER, free ribosomes, Golgi
Serous Cells
- Mucin-secreting cells
- Mucus is stored as mucinogen granules
Mucous Cells
- Contractile cells at basal aspect of acinar secretory cells
- Generate contractile force required for ejection of serous or mucous fluid from glands
Myoepithelial Cells
- leads from the acinus, **most prominent in glands **which produce watery serous secretion **(parotid) **
- furthers from oral caviy, connected to cells producing serous & mucous
Intercalated duct
contains striations (middle portion)
Striated ducts
portion which empties into the oral cavity, connection from where acinus products are produced
Excretory duct
completely serous,
Parotid gland
mixed glands, mostly serous
Submandibular gland
mixed glands, mostly mucus,
Sublingual gland
Combined secretions of all major and minor salivary glands
Saliva
How much saliva per day?
1-2L per day
MOISTEN
Saliva contains ____ which breaks complex carbs down into sugars
α-amylase
dry mouth(xerostomia due to medication or autoimmune disease) can result in ____ lack of saliva
caries outbreak
Saliva is a source of ____ and ____ ions essential for tooth development and maintencnece
Calciuma phosphate ions
Usually occur in major salivary glands
80% are benign
Salivary Gland tumors
gustatory sweating and facial flushing whenever you eat.
Frey Syndrome as aresult of complication of surgucal treatment of salivary gland tumors
Chicken nuggie sweats
- Systemic autoimmune disease
- Dry mouth and eyes
- Alteration of myoepithelial cells reduction in actin (reduces contractile ability of myoepithelial cells, cant push out saliva) in salivary glands
Reduces saliva flow
Primary Sjogren syndrom
- quadrant designated by angles
- 1-8
Palmer system
- two numbers
- first number for quarant (1-4)
- second number for tooth (1-8)
Internantional system
- Numbering start in upper right quadrant
- 1-32
American system