Submandibular Triangle Flashcards
What are the borders of the submandibular triangle?
Base: inferior border of the mandible
Sides: anterior and posterior bellies of digastric
What muscle originates from the styloid process and inserts on the hyoid bone?
Stylohyoid muscle
What structure does the stylohyoid straddle?
Digastric Tendon
The submandibular gland lies on top of what two muscles?
Mylohyoid and Hyoglossus Muscle
What two muscles are deep to the mylohyoid muscle?
Geniohyoid and Genioglossus Muscles
What two muscles are superior to the hyoglossus muscle?
Styloglossus and Palatoglossus Muscles
What are some of the other structures within the submandibular triangle besides the muscles?
Submandibular gland and duct, sublingual gland and ducts, CN 12, Lingual nerve, submandibular ganglion, and lingual artery and vein
Where does the lingual nerve branch from?
From the mandibular (V3) branch of the Trigeminal Nerve (CN 5)
What type of fibers are within the submandibular ganglion?
GVE parasympathetics of CN 7 (facial)
What nerve innervates all intrinsic and extrinsic muscles of the tongue (EXCEPT what other muscle)?
CN 12; Palatoglossus muscle
What are the extrinsic muscles that affect the hyoid bone?
Digastric Muscles and Geniohyoid Muscle
What is the origin and insertions of the mylohyoid muscles?
Origin: Mylohyoid Lines
Insertions: Mylohoid Raphe and Hyoid Bone
What muscle lies on the surface of the mylohyoid muscle?
Anterior belly of the digastric muscle
What nerve innervates the mylohyoid muscle? And what other muscle does this nerve also innervate?
Nerve to mylohyoid; Anterior belly of the digastric
What innervates the posterior belly of the digastric?
Facial Nerve (CN 7)
What accounts for the divergence in innervation of the digastric muscles?
They derive from different pharyngeal arches (I and II)
What muscles attach on the inferior and superior mental spines?
Superior: Genioglossus Muscle
Inferior: Geniohyoid Muscle
Where does the anterior belly of the digastric muscle insert?
Digastric Fossa
Contraction of the geniohyoid muscle will perform what action on the hyoid bone?
Pulls the hyoid bone anterior and superior
What innervates the geniohyoid?
A branch of C1 from the cervical plexus that travels with they hypoglossal nerve.
What are the 4 extrinsic muscles of the tongue?
Genioglossus, hyoglossus, styloglossus, and palatoglossus muscles
Contraction of what fibers of the genioglossus would cause protraction? Retraction?
Inferior fibers; superior fibers
Where does the hyoglossus muscle originate?
Greater horn of the hyoid bone and adjacent body
Where does the palatoglossus muscle originate and what innervates it?
Palatine aponeurosis; CN 10 (vagus)
