submandibular region Flashcards
submandibular region
area between the mandible and hyoid bone and 2 bellies of digastric muscle
muscles in submandibular region
hyoglossus
mylohyoid
geniohyoid
digastric
boundaries of submandibular triangle
anterior: anterior belly of digastric
posterior: posterior belly of digastric and stylohyoid
above: base of mandible
floor of submandibular triangle contains
mylohyoid
hyoglossus
middle constrictor
glands of submandibular region
submandibular and sublingual
apex of parotid
nerves of submandibular region
lingual, hypoglossal, submandibular ganglion, glossopharyngeal, nerve to mylohyoid, and marginal mandibular and cervical branches of facial nerve
arteries of submandibular region
facial and lingual arteries
vein of submandibular region
common facial vein (and internal jugular vein)
lymph nodes of submandibular region
submandibular
the deep part of the submandibular gland is between what two muscles?
hyoglossus and mylohyoid
what kind of gland is the submandibular gland?
mixed-mucous and serous
produces 70% of saliva
two parts of the submandibular gland
- superficial (larger): forms an impression on the medial aspect of the mandible (submandibular fossa)
- deep part (smaller): hooks around the posterior margin of the mylohyoid to enter the oral cavity proper. It lies on the lateral surface of the hyoglossus, lateral to the root of the tongue
submandibular duct
(Wharton’s duct)
5 cm long
-first between mylohyoid and hyoglossus then between sublingual gland and genioglossus.
-opens as 1-3 orifices on a small sublingual papilla (caruncle) at the base of the lingual frenulum bilaterally
what is the lymph drainage of the submandibular gland?
drains to submandibular lymph nodes
whats the dangerous relationship between the submandibular duct and lingual nerve?
lingual nerve hooks around duct
what is superficial to the submandibular gland?
platysma facial vein cervical and marginal mandibular branches of facial nerve submandibular lymph nodes *part of the gland is related laterally to : --mandibular fossa --facial artery --attachment of medial pterygoid
the ____ artery is embedded in the submandibular gland
facial
deep relation of the submandibular gland
mylohyoid vessels, nerve, and muscle lingual nerve and submandibular ganglion hypoglossal nerve submandibular duct hyoglossus muscle deep lingual vein
blood supply of the submandibular gland
- submental arteries which arise from the facial artery; a branch of the external carotid artery
- venous drainage through submental veins which drain into the facial vein and then the internal jugular vein
parasympathetic innervation of submandibular gland
- promotes saliva secretion
- originates from the superior salivatory nucleus through preganglionic fibers via the chorda tympani branch
- chorda tympani joins lingual nerve before synapsing at submand ganglion
- post-gang secretomotor fibers directly induce the gland to produce secretions and vasodilator fibers which accompany arteries to increase blood supply to gland
sympathetic innervation of submandibular gland
- reduces saliva secretion thru vasoconstriction
- decreases volume of salivary secretions, resulting in a more mucus and enzyme rich saliva
- originates from superior cervical ganglion, where post-ganglionic vasoconstrictor fibers travel as a plexus on the internal and external carotid arteries, facial artery and submental arteries to enter each gland
symptoms of lingual nerve injury
immediate post-op ipsilateral parathesia–permanent
-injury of chorda tympani leads to loss of taste from anterior 2/3 of tongue and loss of salivary secretion from submand and sublingual glands
symptoms of hypoglossal nerve
ipsilateral paresis or paralysis of intrinsic muscles of tongue leading to dysarthria and deviation of tongue to side of lesion
-rarely injured
symptoms of facial nerve injury
- (marginal mandibular branch)
- ipsilateral paresis or paralysis of muscles supplying lower lip and chin, including depressor labii inferioris, which presents as drooping of lower lip
- temporary–6-12 weeks
salivary duct calculi
-calculus or sialolith is a calcified deposit which can block the lumen of a duct
why is the submandibular duct the most susceptible to calculi out of all the salivary ducts? (80% of cases)
- torturous length of duct (5 cm)
- ascending secretory pathway
- nature of salivary secretion
salography
- direct injection to salivary gland to examine them
- sialogram=special type of radiograph
- calculus may be present radiographically as stricture or complete occlusion of duct
the smallest salivary gland
sublingual
deepest salivary gland
sublingual
submandibular and sublingual both contribute to only —% of overall salivary volume
3-5%
what kind of secretions does sublingual gland produce?
mixed but predominately mucous
location of sublingual
- almond shaped
- on floor of the oral cavity proper
- under tongue
- bordered laterally by mandible and medially by genioglossus muscle
- the glands form a groove on the medial surface of the mandible (sublingual fossa)
where is the sublingual gland in relation to the submandibular duct?
on medial side of sublingual
-submandibular duct and lingual nerve pass immediately next to sublingual glands between sublingual and genioglossus
both sublingual glands unite anteriorly and form a single mass thru ______ configuration around the _____
horseshoe configuration around the lingual frenulum
sublingual fold
superior aspect of the horeshoe shape
-elevated, elongated crest of mucous membrane
how do secretions from the sublingual gland flow into oral cavity?
minor sublingua ducts (Rivinus**, 8-20 ducts)
each open out onto sublingual folds