Oral cavity part 2 Flashcards
Intrinsic muscles originate and insert within?
substance of the tongue
intrinsic muscles divide into:
superior longitudinal muscles
inferior longitudinal muscle
transverse muscle.
vertical muscle.
function of the intrinsic muscle?
to contribute to the precise movement of the tongue required for speech, eating and swallowing.
what nerve innervates extrinsic muscle( Genioglossus)?
hypoglossal nerve of trigeminal nerve 2
Content of the geioglossus muscle
It is a thick, fan-shaped muscle
that occur on either side 0f the midline septum.
Oring and insertion of the genioglossus muscle
originate: from the mental spines, posterior surface of the mandible.
insert: inferior fibers are attached to the hyoid bone
superior fibers held by the intrinsic muscle.
Hyoglossus
Is a thin, quadrangular shaped muscle.
Innervated by hypoglossal nerve of the trigeminal nerve
origin and insertion of the Hyoglossus muscle?
Origin: Greater horn and body hyoid bone
insertion: between genioglossus and styloglossus
depresses the tongue
what are the important landmarks of the oral cavity?
The lingual artery enters the tongue deep into this muscle.
hypoglossal and lingual nerves also enter the tongue superior to muscle.
what are the important landmarks of the oral cavity?
The lingual artery enters the tongue deep into this muscle.
hypoglossal and lingual nerves also enter the tongue superior to muscle.
Styloglossus muscles, innervation, origin and insertion?
By the Hypoglossal nerve of the trigeminal nerve.
originate: Anterior surface of styloid process of temporal bone.
insertion: lateral surface of tongue where it blends with intrinsic muscle
Action of the styloglossus muscle.
Retracts tongue and pulls back of tongue superiorly
Muscle of soft palate and tongue
Palatoglossus.
innervated by vagus nerve of trigeminal nerve.
The originate and insertion?
Origin: Undersurface of palatine aponeurosis
insertion: Fibers pass anterioinferioly to lateral side of tongue
the function of the palatoglossal nerve
Elevate the back of the tongue, moves palatoglossal arches of mucosa towards the midline, and depress the soft palate.
movements facilitate closing the oropharyngeal isthmus and as a result separate the oral cavity from the oropharynx.
Braches from the external carotid artery adjacent to the tip of greater horn of the hyoid bone. which artery?
Lingual artery
Form and upward bend and then loops down to the ………..
hyoglossus muscle.
THE lingual artery travel forward in plane between which muscles to where
between the hyoglossus and genioglossus muscles to the tip of the tongue
deep lingual vein
Visible through mucosa of the undersurface of the tongue
separated from the lingula artery in the posterior aspect by the hyoglossus muscle
travels with the hypoglossal nerve to the external surface of the hyoglossus
to vein does the Deep lingual vein drains into ?
internal jugular vein
Dorsal lingula vein
followa the lingual artery btween the hyoglossus and genioglossus
drain to the internal jugular vein
taste and general sensation from posterior one-third of tongue comes from whic nerve
the glossopharyngeal nerve of the trigeminal nerve
which nerve also carries parasympathetic and state fibres from oral part of tongue that part is part of facial nerve
lingula nerve
branch of mandibular nerve of CNIX
The facial nerve
taste from the anterior two-third of the tongue
special sensory fibers are received from the chorda tympani branch.
Hypoglossal nerve
innervate all muscle of the tongue
besides palatoglossus
Glands that open or secrete into oral cavity.
salivary glands
Small glands in submucosa or mucosa of the oral epithelium lining the tongue, palate, cheeks and lips, and open directly or via small ducts.
Larger glands in additional to small glands include:
submandibular, paired parotid and sublingual gland
gland that extends outside the boundaries of the oral cavity
Parotid gland
the parotid gland lies in shallow triangular-shaped impression formed:
- sternocleidomastoid posteriorly
2.ramus of the mandible anteriorly - posterior to aspect of Zygomatic arch superiorly.
extends anteriorly and inferiorly over which muscle.?
anteriorly over masseter muscles
inferiorly over the posterior belly of digastric muscle
parotid duct
passes anterior across the masseter muscle
pierces buccinator to open into the cavity.
adjacent to second upper moral tooth.
A hooked shaped gland.
submandibular gland
The larger hook of the mandibular gland
Directed forward in horizontal plane
lies deep to mylohyoid muscle
lies in the submandibular fossa.
Smaller arm of the hook.
loop around posterior origin of mylohyoid muscle
lies within the floor of te oral cavity
lies lateral to the root of the tongue
submandibular duct emerges from and opens where
from the medial part of the deep part of gland
opens on the sublingual papilla beside base of the frenulum of the tongue.
The lingual nerve loops under which duct?
submandibular duct
descends anteriomedially through floor of oral cavity and then ascends into tongue
sublingual gland
almost shaped
immediately lateral to submandibular duct and associated lingual nerve in floor of oral cavity.
where does the sublingual gland lie?
lies in the sublingual fossa
superior to anterior one-third of mylohyoid line
Superior margin raises an elongated fold of mucosa (sublingual fold) which extends from floor of oral cavity to sublingual papilla beside base of frenulum
sulingual gland drains nto what ?
into oral cavity via small ducts which opens into crest of sublingual fold.
occasionally, a major sublingual duct will open with submandibular duct on sublingual papillae.
Temporomandibular joint
Opening and closing of the mouth and complex chewing or side-side movements of lower jaw.
Synovial joint – formed between head of mandible and articular fossa, and articular tubercle of temporal bone
The articular surfaces are covered by ?
Fibrocartilage.
Joint are divided into two parts, the upper and lower by a………… ?
fibrous articular disc
upper- allows head of the mandible to move backward and forward onto articular tubercle causing protraction and retraction of mandible.
lower part- allow hinge-like depression and elevation of mandible.
the membrane that lines all non-articular surfaces of both upper and lower compartments of the joint and is attached to the margins of the articular disc.
synovial membrane.
Fibrous membrane encloses temporomandibular joints complex and is attached:
-superiorly along margin of articular tubercle
-laterally and medially along the margins of articular fossa
-posterior, to the region of tymponosquamous suture
- inferior to upper part of Neck mandible
3 ligamnents are present in the temporomandibular joint name them?
lateral ligaments, sphenomandibular ligament and stylomandibular ligament.
Movements of the Mandible includes:
depression: Digastric, geniohyoid, mylohyoid muscles assisted by lateral pterygoid muscle
Movements of the Mandible includes:
depression: Digastric, geniohyoid, mylohyoid muscles assisted by lateral pterygoid muscle
elevation: temporalis, masseter and medial pterygoid muscles
protraction: lateral pterygoid muscle, assisted by medial muscle.
retraction:geniohyoid and digastric muscle and posterior and deep fibers of temporalis and masseter muscles.
A wedge-shaped fossa
infratemporal fossa.
The roof of the infratemporal fossa
Roof- formed by greater wing of sphenoid+ temporal bones.
foramen ovale , foramen spinosum
communicates with temporal fossa
The lateral wall of the infratemporal fossa
is medial surface of the ramus of mandible
opening to the mandibular canal
medial wall
: Lateral plate of pterygoid process + pharynx and
soft palate (tensor and levator veli palatini)
Communicates with pterygopalatine fossa
Anterior wall
the posterior surface of the maxilla.
communicates with inferior orbital fissure.
name an extracapsular ligament of temporomandibular joint
Sphenomandibular joint.
attachment of the sphenomandibular ligament
to the spine of the sphenoid bone and lingula of mandible and posterior margin of the mandibular foramen
innervation of the infratemporal fossa?
Maxillary artery
Mandibular nerve (CNV3)
Facial nerve (CNVII) branches
Glossopharyngeal nerve (CNIX)
Pterygoid plexus
Mandibular nerve of the trigeminal
Gives of motor and sensory
all branches originate from infratemporal fossa.
The Sensory innervation comes from and enters Where between muscles.
from foramen ovale and enters the infratemporal fossa. Between tensor veli palatini and lateral pterygoid muscles.
Meningeal branch
Nerve to medial pterygoid
The anterior and posterior trunks of the mandibular nerves
Anterior Trunk
Buccal, masseteric, deep temporal nerve and nerve to lateral pterygoid
Posterior Trunk
Auricotemporal, lingual and inferior nerves
Auriculotemporal nerve
Originates as two roots, which pass posteriorly to middle meningeal artery as it ascends to foramen spinosum.
Ascends between tensor veli palatini and lateral pterygoid muscle
Curves around neck of mandible
Ascends deep to parotid gland, between temporomandibular joint and ear
what does the auriculotemporalis supply to the skin over temple, external ear, external auditory meatus and TMP
general sensation.
Carries parasympathetic fibres from CNIX to parotid gland
General sensation to anterior two-thirds of tongue, oral mucosa on floor of oral cavity
is given by which nerve?
Lingual nerve
lingual nerve is joined by ……….branch of facial nerve in the infratemporal fossa.
Chorda tympani
how does the lingual nerve supplies and get to the oral cavity.
Descends between tensor veli palatini and lateral pterygoid.
Descends across the medial pterygoid muscle to enter the oral cavity.
Passes into the tongue on the lateral surface of the hyoglossus and attaches to the submandibular ganglion.
as it enters the oral cavity/ floor it lies immediately to what?
inferior to the last molar tooth
Palpable through oral mucosa
Risk of injury to operations to molar teeth and gingivae
the origin of the maxillary artery?
Originates within substance of parotid gland, enters infratemporal fossa between neck of mandible and sphenomandibular ligament
Passes through infratemporal fossa to enter pterygopalatine fossa to give rise to terminal branches
the 3 parts of the maxillary artery
First part: between neck of mandible and sphenomandibular ligament
Middle meningeal
Inferior alveolar arteries
Second part: related to lateral pterygoid muscle
Deep temporal, masseteric, buccal and pterygoid branches
Third part: in pterygopalatine fossa
Network of veins between lateral and medial pterygoid muscles as well as lateral pterygoid and temporalis muscles is called
pterygoid plexus
