Anatomy Of Salivary Glands Flashcards
3 major salivary glands
Bilateral pairs;
Parotid glands
Submandibular glands
Sublingual glands
When do the salivary glands form?
First 4-6 weeks of development
Position of the parotid glands
Below external auditory meatus (ear)
Between mastoid process and posterior border of ramus
Parotid gland saliva volume and constituency
25% total saliva volume
100% serous saliva
Parotid gland ducts
Stensens OR parotid duct
5cm long
Runs from; gland outside masseter muscle, parallel and 1cm below zygomatic arch
Opens buccally upper first molar regions
Parotid gland nerve innervation
Glossopharyngeal (autonomic)
Auriculotemporal (sensory)
Intimately associated with the Facial
nerve
Position of submandibular gland
Between body of mandible and mylohyoid muscle, in submandibular fossa
Submandibular gland saliva volume and composition
60-65% total saliva volume
Mixed serous and mucous saliva secretions
Submandibular gland duct
Wharton’s duct
5cm long
Opens under anterior part of tongue, lateral to lingual fraenum at sublingual caruncle
Submandibular gland nerve innervation
Chorda tympani (branches from facial nerve)
Lingual branch of the inferior dental nerve
Position of sublingual gland
Floor of mouth in the sublingual fossa
Sublingual gland saliva volume and composition
5-10% total saliva volume
60% mucous saliva
Sublingual gland duct
Bartholin’s duct
10-20 smaller ducts (Rivinus ducts) open along the sublingual fold
Sublingual gland nerve innervation
Chorda tympani (branches from facial nerve)
Lingual branch of the inferior dental nerve
What are the new discovery glands and where are they located
Tubarial glands
Located in nasopharynx
Saliva volume and composition of minor salivary glands
Less than 10% total saliva volume
Mixed saliva, mainly mucous
Produce lots of salivary proteins
How are the minor salivary glands named
According to location; Labial, buccal, palatine, lingual
Minor salivary glands nerve innervation
Parasympathetic innervation
Sympathetic innervation
Minor salivary gland ducts
Numerous small groups of secretory units opening via short ducts directly into the mouth.
What lines the ducts and protects the saliva?
Epithelium
What surrounds the epithelium, protecting and supporting the gland?
Connective tissue
2 types of connective tissue
Capsule - surrounds the outer portion of gland
Septum - divides inner portion of gland into lobes and lobules
What do the capsule and septum do?
Carry nerve and blood to supply the cells.
Adenomeres
Working part of salivary gland and surrounded by connective tissue
What are within the adenomeres and what does their base rest against?
Secretory cells - acini
Their base rests against surrounding connective tissue
2 classifications of acini
Mucous acini
Serous acini
(Or mixture of both)
Functions of serous saliva
Lubricating food
Enzymic action begins digestion
Removing epithelial debris
Diluting food
Serous secretory cells
Serous acini
Mucous secretory cells
Mucous acini
Which secretory cell has a wider lumen
Mucous acini
Functions of mucous saliva
Binding food into a bolus
Protect the oral cavity against frictional abrasion
Lubrication
What is formed in a mixed serous-mucous acini
Serous demilune around mucous secretory cells
Myoepithelial Cells
Embrace the acini secretory cells, contracting and squeezing, forcing the saliva out of the lumen and into the ducts
Acinar Fluid
Consists of;
Water
Inorganic Ions
Small molecules and products synthesised by cells (mucoproteins and amylase)
What follows the secretory end piece
Ducts
3 different types of duct
Intercalated
Striated
Excretory
Structure of intercalated duct
Simple cuboidal epithelial cells
Structure of striated ducts
Simple columnar epithelial cells with basal striations
Which ducts aids in the modification of saliva
Striated duct
What type duct does the saliva exit into the oral cavity
Excretory duct (terminal)
Structure of excretory duct
Lined by pseudostratified columnar epithelium, then changes to stratified cuboidal and finally stratified squamous epithelium at its opening.
Blood supply
Supplied by external carotid artery and facial lingual artery.
Vessels and nerves enter at hilum.
2 capillary networks; one for secretory end piece and one for ducts.
Control of salivation
Salivary nuclei in brain are stimulated by taste, smell, thoughts.
Triggers neurotransmitter release from nerve endings of salivary glands.
What can cause obstruction
Caniculi - calcium deposits in ducts, common in submandibular and can lead to infection.
Cysts - trauma to salivary gland causing accumulation of saliva in surrounding tissue.
2 types of cysts
Mucocele - minor glands
Ranula - major glands in the floor of the mouth (could be submandibular or sublingual)
What causes hyposalivation
Medications or tablets
Radiotherapy
Autoimmune diseases
Diabetes
Salivary stones (can cause severe pain when eating)
What can irradiation of head and neck cause
Destroys secretory cells (atrophy) and leads to xerosomia
Causes of xerostomia
Emotional disturbances - anxiety
Mouth breathing
Smoking
Drugs
Talking for long periods
Medical condition/medication
Caniculi
- Calcium deposit formation in salivary duct.
- Common in submandibular.
- Can lead to; infection, inflammation, blocked duct/gland.
Mucocele
Trauma to minor salivary glands causing accumulation of saliva and surrounding tissue; cyst.
Clinical appearance of Mucocele
Moveable
Painless
Soft round dome
Pearly/semi clear or blueish
Ranula
Trauma to major salivary glands on floor of mouth, balloon of saliva; cyst.
Can lead to obstruction of the gland/duct.
Acute viral infection causing inflammation and painful swelling of the parotid glands
Mumps
Inflammation of minor salivary glands on palate in response to heat from tobacco
Nicotine stomatitis
Painless bilateral swelling of parotid glands not caused by inflammation or infection
Sialosis
Neoplasms
Tumours
(Benign or malignant)
Oral symptoms of Sjögren’s syndrome
- mild erythema and thinning of mucosa.
- erythema, fissuring, coating and depapillation of dorsum of tongue.
- traumatic erosions and lesions; ulcers, angular chelitis.
- thickened saliva
What saliva is viscous mucin rich?
Mucous saliva
What saliva is watery?
Serous saliva
