SALIVARY GLANDS
- Salivary glands secrete saliva into oral cavity
- Saliva :
- Clear, tasteless & odorless fluid
- keeps mouth's mucosa hydrated
- Lubricate food
- Makes swallowing easier.
- Starts digestion of strach.
- bec. it contains amylase enzyme
Parotid gland: (pair)
- The largest of the three paired salivary glands
- Triangular in shape.
Position:
- Anterior and below the lower half of the ear
Coverings:
- False Capsule: formed by the investing layer of deep cervical fascia
- True capsule: Condensation of the fibrous stroma of the gland
It has 3 surfaces & 3 bordars:
Structures within the parotid gland :
- External Carotid artery (the deepest structure)
- Retromandibular vein (it is formed within the gland by union of maxillary and superficial temporal vein).
- Facial nerve (most superficial structure) (runs horizontally)
- It enters the gland and divide within its substance giving 5 terminal branches).
Submandibular gland :
- Located within the submandibular triangle of the neck,
Structure :
Each submandibular gland has :
- 1. Superficial loob
- 2. Deep loob
seperated by the mylohyoid muscle.
- Each gland has submandibular duct or Wharton's duct:
- Starts from anterior end of deep part of the gland .
- 2 inches long.
- excretes the contents of the gland onto the floor of the oral cavity.
- It runs on hyoglossus muscle, situated btw 2 nerves (lingual & hypoglossal)
- Then runs btw. sublingual gland and genioglossus muscle.
- It opens on the summit of sublingual papilla.
Blood Supply of submandibular glands :
- Facial & lingual arteries
- Facial & lingual veins.
Sublingual gland :
- Have almond-shaped.
- Lie on the floor of the oral cavity.
- They are situated underneath the tongue, bordered laterally by the mandible and medially by genioglossus muscle.
Both sublingual glands unite anteriorly and form a single mass through a horseshoe configuration around the lingual frenulum. The superior aspect of this U-shape forms an elevated, elongate crest of mucous membrane called the sublingual fold (plica sublingualis). Each sublingual fold extends from a posterolateral position and traverses anteriorly to join the sublingual papillae at the midline, either side of the lingual frenulum.
Blood Supply :
Blood supply is via the sublingual and submental arteries which arise from the lingual and facial arteries respectively; both of the external carotid artery.
Venous drainage is through the sublingual and submental veins which drain into the lingual and facial veins respectively; both then draining into the internal jugular vein.
+ Blood Supply of parotid gland :
By the posterior auricular & superficial temporal arteries