2. Saliva Flashcards
Introduction
Why is saliva important
• Saliva functions primarily to prevent ____ of the oral mucosa and to provide ____ for the mastication and swallowing of ingested food. The senses of taste and, to a lesser extent, smell depend on an adequate supply of saliva.
• Saliva plays a very important role in maintaining proper oral ____. It accomplishes this task by washing away food particles, killing bacteria (lysozyme and IgA activity), and contributing to overall dental integrity.
dehydration
lubrication
hygiene
Introduction
Salivary flow • Normally ~\_\_\_\_L secreted per day • Amount of saliva varies with eating Generally ~\_\_\_\_mL/min When stimulated can be \_\_\_\_ mL/min • Decreased saliva > \_\_\_\_ • Excess saliva > \_\_\_\_
1-1.5 0.3-0.5 4-8 xerostomia drooling
Salivary Glands
• Major ____
____ ____
• Minor
submandibular
sublingual
parotid
Introduction
Exocrine glands
• The major salivary glands are ____ glands: specialized secretory organs that contain a ____ ductular system through which they release their secretory products.
compound exocrine
branching
Introduction
Exocrine glands
• The salivary glands are divided into ____, each of which are drained by a single ____.
• Within the lobules reside the secretory units of the gland. Each secretory unit is composed of an ____ and a ____.
• The acinus represents a cluster of 15 to 100 ____ cells that synthesize and secrete proteins into the lumen of the epithelial structure
lobules intralobular duct acinus small intercalated acinar
Introduction
Exocrine glands
• Acinar cells from the salivary glands also secrete an ____, plasma-like fluid that accompanies the secretory proteins.
• In all, the final acinar secretion is a ____- rich product known as the ____ secretion.
isotonic
protein
primary
Introduction
Acinar cells
Different salivary acinar cells secrete different proteins.
• The acinar cells of the parotid secrete a ____ (watery) product that contains an abundance of ____.
• Many acinar cells of the sublingual glands secrete a mucinous product that is composed primarily of ____ glycoproteins.
• The submandibular gland contains both ____-type and ____-type acinar cells.
serous alpha-amylase mucin mucous serous
Introduction
Exocrine Glands
• Each acinar lumen is connected to the ____
end of an intercalated duct.
• Distally, the intercalated ducts fuse with other small ducts that coalesce to form the ____ that drains the lobule.
• The ducts not only provide a conduit for the transport of secretory proteins, but the epithelial cells lining the ducts also ____ the fluid and electrolyte composition of the primary secretion.
• Thus, the final exocrine gland secretion represents the combined product of two distinct epithelial-cell populations, the ____ cell and the ____ cell.
intercalated duct intralobular duct modify acinar duct
Anatomy
Parotid gland
• The ____ of all the major salivary glands.
• ____ in shape, with up to 5 processes (or extensions).
• The gland’s capsule is from the ____.
• Approximately 75% of the parotid gland overlies the ____ muscle; the rest is ____.
largest
pyramidal
deep cervical fascia
retromandibular
Anatomy
Parotid gland
• The facial nerve enters the parotid fossa by passing between the stylohyoid muscle and the posterior belly of the digastric muscle, then splits the gland into a ____ lobe and a ____ lobe that are connected by an ____.
• The deep lobe lies adjacent to the ____ space (note: pathology of the deep lobe will only be visible ____).
• Although it passes through the parotid gland, the facial nerve does not provide any ____ to it.
superficial deep isthmus pharyngeal intraorally innervation
Anatomy
Parotid duct
• Forms within the ____ lobe and passes from the anterior border of the gland across the masseter superficially, through the buccinator into the oral cavity opposite the ____.
• Also known as ____ duct
deep
second maxillary molar
stensen’s
Anatomy
Arterial Supply of the Parotid Gland
• The external carotid artery: It ascends superiorly posterior to the ____ and deep to the posterior belly of the ____ muscle and the stylohyoid muscle to enter the ____ gland.
• Within the parotid gland, it gives branches to the gland: The ____ artery and the ____ artery.
mandible digastric parotid posterior auricular superficial temporal
Anatomy
Venous Drainage of the Parotid Gland
• The retromandibular vein: Arises from the joining of the ____ and ____ veins within the parotid gland.
superficial temporal
maxillary
Anatomy
Sensory Nerves of the Parotid Gland
• Sensory innervation is supplied by the ____ nerve (deep gland) and the ____ nerve (superficial gland and fascia).
auriculotemporal
great auricular
Anatomy
Parasympathetic Innervation of the Parotid Gland
• The parasympathetic innervation to the parotid gland has a complex path. It begins with the ____ nerve (cranial nerve IX).
• This nerve synapses with the ____.
• The ____ nerve then carries parasympathetic fibers from the otic ganglion to the ____ gland.
• Parasympathetic stimulation causes an ____ in saliva production.
glossopharyngeal otic ganglion auriculotemporal parotid increase
Anatomy
Sympathetic Innervation of the Parotid Gland
• Sympathetic innervation originates from the ____, part of the paravertebral chain.
• Fibers from this ganglion travel along the ____ artery to reach the parotid gland.
• Increased activity of the sympathetic nervous system ____ saliva secretion, via ____.
superior cervical ganglion
external carotid
inhibits
vasoconstriction
Anatomy
Submandibular gland
- the ____ largest salivary gland
• It is located superior to the ____ muscle and is divided into superficial and deep lobes, by the ____ muscle. The ____ lobe comprises most of the gland.
• The superficial lobe is located in the ____ triangle and is surrounded by the investing layer of deep cervical fascia.
second
digastric
mylohyoid
superficial
submandibular
Anatomy
Submandibular Gland
Anatomy
- Deep portion of the submandibular gland lies in the oral cavity between the ____ muscle and the mandible and ends at the posterior border of the ____ gland.
- The facial ____ crosses between the submandibular gland and the mandible, while the facial ____ normally lies superficial to the gland.
- The submandibular duct lies along the ____ gland and empties into the oral cavity at the ____.
hyoglossus sublingual artery vein sublingual sublingual papilla
Anatomy
Submandibular Duct
• Also know as ____ Duct.
• The submandibular duct lies along the ____ gland and empties into the oral cavity at the ____.
wharton’s
sublingual
sublingual papilla
Anatomy
Sublingual gland
• ____ of the 3 major salivary glands.
• Located in the oral cavity between the mucosa of the oral cavity and the ____ muscle.
• Creates a ____ fold in the floor of the oral cavity.
• Lies between the ____ of the mandible and the ____ muscle of the tongue.
smallest mylohyoid sublingual sublingual fossa genioglossus
Anatomy
Sublingual ducts
• Numerous small ducts opening along the ____.
• ____ duct may be present – it is a common duct that drains the ____ part of the gland in the region of the sublingual papilla.
sublingual gold
bartholin’s
anterior
Anatomy
Arterial Supply of the Submandibular & Sublingual Gland
• The gland receives its blood supply from the ____ arteries.
facial and lingual
Anatomy
Venous Drainage of the Submandibular & Sublingual Gland
• The venous drainage is via the common ____ veins.
facial and lingual
Anatomy
Parasympathetic Innervation of the Submandibular & Sublingual Gland
- Parasympathetic innervation to the submandibular glands is provided by the ____ nucleus via the ____ branch of the ____ nerve synapsing on the ____.
- Increased parasympathetic activity ____ the secretion of saliva.
superior salvatory
chorda tympani
submandibular ganglion
promotes
Anatomy
Sympathetic Innervation of the Submandibular & Sublingual Gland
- Sympathetic innervation originates from the ____, where post-synaptic vasoconstrictive fibers travel as a ____ on the internal and external carotid arteries, facial artery and finally the ____ arteries to enter each gland.
- Increased sympathetic drive reduces glandular ____ through vasoconstriction and decreases the ____ of salivary secretions, resulting in a more mucus and ____-rich saliva.
superior cervical ganglion plexus submental bloodflow volume enzyme
Anatomy
Innervation of Major Glands Summary
• Parasympathetics (Rest and Ruminate)
-____ of salivary flow.
-Superior and inferior salivatory nucleus in the dorsal pons giving general visceral efferent fibers to the ____ and ____ nerve, respectively.
-CN VII via the ____, to the ____ ganglion, then to the ____ and sublingual glands. -CN IX via the ____ nerve, to the ____ganglion, then to the parotid gland via the ____ nerve.
• Sympathetics (Fight or Flight)
- ____ salivary flow, but stimulates protein rich saliva.
- T1-T3 nerves to the ____, to carotid and ____ or lingual arteries.
stimulation
facial
glossopharyngeal
chorda tympani submandibular submandibular lesser petrosal otic auriculotemporal
slows
superior cervical ganglion
facial
Anatomy
Minor salivary glands
• Found throughout the oral cavity (buccal, labial, palate, lingual), except the ____ and ____.
• Approximately 1000 glands.
• Small lobules of secretory glands with ducts.
• Located in the ____.
• Innervated by the ____ nerve like the ____ and ____ glands.
anterior plate
gingiva
submucosa
facial
submandibular
sublingual
Physiology Contribution to Salivary Flow • Submandibular- \_\_\_\_% • Sublingual- \_\_\_\_% • Parotid- \_\_\_\_% • Minor- \_\_\_\_%
60
5
30
5
Physiology Saliva Composition • \_\_\_\_% water • 1% organic/inorganic compounds Electrolytes Mucous Proteins/Enzymes
99
Physiology Serous Cells • \_\_\_\_, protein rich-rich fluid • Secrete enzymes \_\_\_\_ Lysozyme • \_\_\_\_ • Lactoferrin
watery
amylase
IgA
Physiology
Mucous cells
• Viscous product- ____ Highly ____ proteins Gel-like lubrication
• Rich in ____ and glycoproteins (mucins)
• Contains
____
Immunoglobulins
Lactoferrin
mucin
glycosylated
carbohydrates
lysozyme
Physiology Gland Secretion • Parotid- Mostly \_\_\_\_ • Submandibular- \_\_\_\_ serous and mucous • Sublingual- Mostly \_\_\_\_ • Minor- Mostly \_\_\_\_
serous
mixed
mucous
mucous
Physiology
Exocrine glands
• Salivary glands contain a rich supply of nerves and blood vessels. Postganglionic parasympathetic and sympathetic fibers contribute to the autonomic regulation of secretion.
• The major agonists of salivary acinar secretion are ____ and ____, which are released from postganglionic parasympathetic and sympathetic nerve terminals, respectively.
acetylcholine
norepinephrine
Physiology
Exocrine glands
• The cholinergic receptor on the salivary acinar cell is the ____ glandular subtype.
• The adrenergic receptors identified on these cells include both the ____ subtypes.
M3
alpha and beta
Physiology
Parasympathetic control
• Parasympathetic nerves secrete ____ on acinar cells.
• Binds to muscarinic receptors causing increased ____ into the cell via ____ pathway.
• Increased ____ causes vesicles to fuse with the cell membrane, releasing contents into the lumen.
• Calcium also causes release of ____ which ____ blood vessels and increased capillary permeability.
ACh calcium IP3/DAG calcium bradykinin vasodilates
Physiology
Parasympathetic control
• Clinically, some medications have ____ properties that are most commonly manifested as dry mouth.
• Conversely, excessive salivation is induced by some ____ agents that can be found in certain ____ and nerve gases.
anticholinergic
anticholinesterase
insecticides
Physiology
Sympathetic control
• Activated by norepinephrine which leads to calcium ____ and protein ____.
• Norepinephrine causes ____ and ____ fluid flow.
influx
secretion
vasoconstriction
decreased
Physiology
Primary secretion
• The primary secretion of the salivary acinar cell is ____ and results largely from the basolateral uptake of ____ through Na/K/Cl cotransporters, working in conjunction with ____ pumps and basolateral ____ channels.
isotonic
Cl-
Na-K
K+
Physiology
Primary secretion
• The ____ modify the composition of the isotonic, plasma- like primary secretion of the acinar cells.
• As the fluid exits the salivary acinus, it passes through an intercalated duct, with typical intercalated duct cells.
• Later, abundant mitochondria and infoldings of the basolateral membrane give the basal portion of the duct cells a characteristic ____ appearance—hence the term striated duct cell.
ducts
striated
Physiology
Primary secretion
• In general, salivary duct cells absorb ____+ and ____− and, secrete ____+ and ____-.
• Because the epithelium is not very water permeable, the lumen thus becomes ____.
Na Cl K HCO3 hypotonic
Physiology
Salivary electrolytes
- ____ in the gland
- ____ in the mouth
- ____ in calcium and phosphate
- Variable with flow: At low (basal) flow rates, Na+ and Cl− are ____ from the lumen and K+ is ____. At higher flow rates, the composition of the final secretory product begins to approach that of the plasma-like ____ secretion.
isotonic hypotonic high absorbed secreted primary
Physiology
Central control
• Both ____ input and ____ input to the salivatory nuclei can regulate the parasympathetic signals transmitted to the glands.
• Taste and tactile stimuli from the tongue are transmitted to the ____, where their signals can excite the ____ nuclei and stimulate salivary gland secretion.
• Central impulses triggered by the sight and smell of food also excite the salivatory nuclei and can induce ____ before food is ingested. (Ivan Pavlov conditioned dogs to salivate at the sound of a bell).
local
central
brainstem
salivatory
salivation
Physiology
Digestive function
- ____ for bolus formation
• a-amylase (ptyalin)- from ____ cells.
• Lingual lipase- from ____ glands (surrounding the circumvallate and foliate papilla).
• Dissolves food, liquid medium allowing interaction with taste buds.
lubrication
serous
von ebner’s
Physiology
Protective function
• Lubrication to ease swallowing, protection from trauma
• Remineralization
____ with calcium and phosphate (statherins)
____ bind calcium allowing high levels in saliva
• Dilution of heat/cold/toxins/bacteria
• Buffering
pH ____
Bicarbonate
Prevents ____ of enamel (critical pH of ____)
supersaturated PRPs 6.2-7.4 demineralization 5.5
Physiology
Protective function
• Antimicrobial
____- binds iron and is antibacterial
____- kills bacteria, muramidase cleaving NAM/NAG
____-inhibits bacterial growth by disrupting glycolytic pathway
____- particle accumulation, antiviral
____- antimicrobial/antiviral, blocks attachment of microbes to mucosa
____- antimicrobial/antifungal, binds cell membranes
lactoferrin lysozyme peroxidase agglutinin secretory IgA histatins
Clinical Correlations
Tumors of the Parotid Gland
• 80% of parotid tumors are ____. The most common benign tumor is a ____.
• When examining the patient, tumors of the superficial lobe will appear to obstruct view of the ____. Tumors of the deep lobe will appear as ____ swelling adjacent to the lateral pharyngeal space.
• If you see facial nerve palsy and a mass – concern for ____ should be high.
• The most common parotid gland malignancy is ____.
benign pleomorphic adenoma earlobe intraoral malignancy mucoepidermoid carcinoma
Clinical Correlations
Frey’s Syndrome
- Caused by regeneration of the ____ autonomic fibers in an abnormal fashion, innervating the sweat glands near the parotid gland after a parotidectomy.
- Symptoms include ____ and ____ in the distribution of the auriculotemporal nerve during eating.
- Diagnosis is via ____ test–creates a ____ spot over the gustatory sweating area.
- Treatments include tympanic ____ (severing the parasympathetic component) and the topical anticholinergic ____ (Robinul).
auriculotemporal sweating redness minor's starch iodine dark neurectomy glycopyrrolate
Clinical Correlations
Submandibular Sialolithiasis
• A calculus or sialolith is a calcified deposit which can block the lumen of a duct.
• The ____ duct is the most susceptible to calculi out of all the salivary ducts; accounting for approximately 80% of cases.
• This is thought to be due to the ____ length of the duct (5cm), ascending secretory pathway and nature of salivary secretion.
• The submandibular glands and the patency of the ducts can be examined by a ____. A calculus may present radiographically as a stricture or complete occlusion of the duct.
submandibular
torturous
sialogram
Clinical Correlations
Mucocele of Minor Salivary Glands
• A mucocele (aka mucous retention cyst, mucous extravasation cyst) is a clinical term that refers to two related phenomena:
Mucus ____ phenomenon Mucus ____ cyst
- The mucocele has a ____ translucent color, and is more commonly found in ____ and young adults.
- Although the term cyst often used to refer to these, mucoceles are not true cysts because there is no ____ lining.
extravasation retention bluish children epithelial
Clinical Correlations
• A ranula is a type of mucocele (mucous cyst) that occurs in the ____ of the mouth inferior to the tongue.
• It is the most common disorder associated with the ____ glands due to their higher mucin content in secretions compared to other salivary glands.
• Ranulas can be caused by trauma to the delicate ____ gland ducts causing them to rupture, with mucin then collecting within the connective tissues to form a cyst.
• Mucin from the gland or ducts may collect inferiorly beneath mylohyoid and present as a ____ in the neck (a cervical/ plunging ranula). Rarely, this collection can course posteriorly into the ____ space.
floor sublingual sublingual swelling parapharyngeal
