Sem 2 - Y - Tongue and Palate - Oral cavity, salivary glands, tongue/extrinsic/intrinsic muscles/neurovascular, palate, teeth Flashcards
Two arches bind the soft palate to the tongue and the pharynx
- What are these arches known as?
- What muscles form these arches?
- What is found between these arches?
- Palatoglossal arch anteriorly formed by the palatoglossus muscle
- Palatopharyngeal arch posteriorly formed by the palatopharyngeus muscle
Between the palatoglossal and palatopharyngeal arch lies the palatine tonsil
What forms the different boundaries of the oral cavity?
- * Roof
- * Lateral walls
- * Floor
- Roof - the roof of the oral cavity is formed by the hard and soft palate
- The lateral walls of the oral cavity is formed by the buccinator muscle
- The floor of the oral cavity is formed by the two mylohyoids forming an almost sling like structure (geniohyoid contributes)
Describe the attachment, function and nerve supply of geniohyoid and mylohyoid
Geniohyoid - From the inferior genial tubercles of the mandible to the hyoid bone -
- Depresses the mandible and raises the hyoid bone -
- Innervated by nerve to geniohyoid (C1) which travels within the CN XII
Mylohyoid - From the mylohyoid line of the mandible to the hyoid bone - two muscles join medially at a raphe to form a sling -
- Depresses the mandible and raises the hyoid bone -
- Innervated by nerve to mylohyoid from inferior alveolar division of CN V3
State the names of the suprahyoid muslces and their nerve supply
- * Mylohyoid and anterior belly of digastric - supplied by the nerve to mylohyoid branch of the inferior alveolar branch of CN V3
- * Stylohyoid and posterior belly of dgastric - supplied by the posterior auricular branch of the facial nerve
- * Geniohyoid - supplied by nerve to geniohyoid (C1) fibres carried within the hypoglossal nerve
Where do the parotid, submandibular and sublingual ducts open? What is the nerve supply to each of these ducts?
- * Parotid gland empties via parotid duct at the upper 2nd molar - innervated by CN IX, fibres hitch a ride on auriculotemporal nerve
- * Submandibular gland empties via submandibular duct either side of the frenulum between the 1st and 2nd incisors.
- Sublingual gland opens as lots of small ducts into the floor of the mouth
Submandibular and sublingual glands are supplied by the chorda tympani branch of the facial nerve (CN VII)
- What is the general sensory supply to the tongue and special sensory to the tongue?
- Which duct runs with the general sensory to the anterior 2/3rds of the tongue?
- What is the arterial supply to the tongue?
- Where does this branch from?
Anterior 2/3rds - general sensory from lingual nerve branch of CN V3 (posterior division) and special sensory from chorda tympani nerve (CN VII)
Posterior 1/3rds - general & special sensory from CN IX
Lingual nerve runs with the submandibular duct Lingual artery from anterior surface of ECA supplies the tongue
What divides the anterior 2/3rds and posterior 1/3rds of the tongue?
What are the different papillae of the tongue known as? Which is not associated with taste buds?
The anterior 2/3rds and posterior 1/3rds of the tongue are divided by the v-shaped terminal sulcus
- At the apex of this sulcus is the foramen caecum
Lingual paillae - filiform, fungiform, vallate and foliate
- Only filiform is not assocated with taste buds
Where are the lingual and palatine tonsils found?
The lingual tonsil is embeded into the posterior aspect of the tongue itself
The palatine tonsil is found in the tonsillar fossa between the palatoglossal and palatopharyngeal arches
What is the difference in function of the intrinsic and extrinsic muscles of the tongue? What is the difference in attachment?
Intrinsic muscles of the tongue originate and insert into the tongue and change the shape of the tongue
Extrinsic muscles of the tongue begin outside the tongue and embed into the tongue changing the position of the tongue in the mouth
- What are the names of the intrinsic muscles of the tongue?
- How are they named?
- What is their nerve supply?
The intrinsic muscles of the tongue originate and insert into the tongue
The four paired intrinsic muscles of the tongue are named according to the direction in which they travel.
- Superior longitudinal muscles
- Transvere muscles
- Vertical muscles
- Inferior longitudinal muscles
All supplied by the hypoglossal nerve (CN XII)
The extrinsic muscles of the tongue originate outside the tongue and embed into the tongue What is their names and nerve supply?
Innervated by the hypoglossal nerve (CN XII)
- * Genioglossus
- * Styloglossus
- * Hyoglossus
Innervated by the vagus nerve (CN X) in the pharyngeal plexus
- * Palatoglossus
State the attachment and function of the genioglossus muscle?
Genioglossus attaches from the superior genial tubercles on the mandible and into the tongue
- Genioglossus can depress the tongue and protrude the tip of the tongue
State the attachment and function of the hyoglossus muscle?
Hyoglossus attaches from the hyoid bone upwards towards the base of the tongue
- Hyoglossus can depress the tongue
State the attachment and function of the styloglossus muscle?
Styloglossus attaches from the styloid process of the temporal bone to the tongue it can elevate and retract the tongue
State the attachment and function of the palatoglossus muscle?
Palatoglossus attaches from the palatine aponeurosis to insert onto the tongue
- It functions to depress the soft palate and move it to seal the oropharynx during swallowing as well as to elevate the tongue
State the attachment, function and nerve supply of the extrinsic muscles of the tongue
- Supplied by CN XII
- * Genioglossus - From superior genial tubercles of mandible to the tongue - Depresses the tongue and protrudes the tip of the tongue
- * Hyoglossus - From the hyoid bone towards the base of the tongue - Depresses the tongue
- * Styloglogssus - From styloid process of the temporal bone to the tongue - Elevate and retract the tongue
- Supplied by CN X in the pharyngeal plexus
- * Palatolgossus - From palatine aponeurosis to tongue - Elevate the tongue and move the soft palate
Lingual artery is the 2nd anterior branch of the external carotid artery Describe how it reaches the tongue?
Lingual artery will arise close to the hypoglossal nerve
It will then pass deep to the hyoglossus muscle and travel towards the tongue giving off different branches
What are the lingual veins draining the tongue known as? What muscles do they pass deep to/on top off? What do they drain into? Which vein runs alongside the hypoglossal nerve?
Dorsal lingual vein passes deep to the styloglossus
Deep lingual veins deep to the hyoglossus
Sublingual veins pass on top of the hyoglossus
- They all drain into the internal jugular vein via the lingual vein
- The venae commitantes of the hypoglossal nerve drains the sublingual vein
State the nerve supply to all the muscles of the tongue
Which part of the tongue gets a small amount of taste and sensation from what branch of the vagus nerve?
All muscles of the tongue - CN XII except palatoglossus which is innervated by CN X in the pharyngeal plexus
A small amount of taste and sensation is supplied to the posterior 1/3rd of the tongue by the internal laryngeal branch of the superior laryngeal nerve from the vagus nerve
How does the lingual nerve reach the tongue again?
The lingual nerve will branch from the posterior divsiion of the mandibular nerve in the infratemporal fossa.
It will travel through the submandibular gland with the submandibular duct before reaching the tongue
Describe the lymphatic drainage of the tongue?
- Tip of the tongue drains to the submental nodes
- Sides of the anterior 2/3rds of the tongue drains to the submandibular nodes
- Midline of the anterior 2/3rds of the tongue drains to the inferior deep cervical lymph nodes
- Posterior 1/3rd of tongue drains to the superior deep cervical lymph nodes
What bones make up the hard palate?
The maxilla makes up the anterior portion of the hard palate The palatine bones make up the posterior portion of the hard palate
What are the three main foramen in the hard palate? What do these foramina allow to travel through?
- Incisive foramen - anterior in the midline of the hard palate transmitting the nasopalatine nerve
- Greater palatine foramen - posteriorly transmitting the greater palatine nerve and arteries
- Lesser palatine foramen - posteriorly transmitting the lesser palatine nerve and arteries
Which cranial nerve provides sensory innervation to the hard palate? Try and state specific nerves
CN V2 provides sensory innervation to the hard palate (nasopalatine, greater palatine and lesser palatine nerves)
The soft palate is located posteriorly. It is mobile, and comprised of muscle fibres covered by a mucous membrane. Anteriorly, it is continuous with the hard palate and with the palatine aponeurosis. The posterior border of the soft palate is free (i.e. not connected to any structure), and has a central process that hangs from the midline
- * What is this central process known as?
- * What forms the arches connecting the soft palate to the tongue and pharynx?
Central process that hangs down from the midline of the soft palate is the uvulua
Arches connecting the soft palate to the tongue and pharynx:
- Palatoglossal arch - formed by palatoglossus
- Palatopharyngeal arch - formed by palatopharyngeus
What are the muscles of the soft palate? What is the nerve supply to these muscles?
Tensor veli palatini - innervated by branches from nerve to medial pterygoid from the main trunk of CN V3
Innervated by vagus nerve in the pharyngeal plexus:
- * Levator veli palatini
- * Palatoglossus
- * Palatopharyngeus
- * Musculus uvulae
Which muscle of the soft palate has a tendon that curves around the pterygoid hamulus of the medial pterygoid plate of the sphenoid bone?
The tendon of the tensor veli palatini curves around the pterygoid hamulus to reach the palatine aponeurosis
What is the attachment and function of the tensor and levator veli palatini?
- Tensor veli palatini attaches from the medial pterygoid plate of the sphenoid bone and eustachian tube, then curves around the pterygoid hamulus and inserts into the palatine aponeruosis - tenses the soft palate
- Levator veli palatini arises from the petrous part of the temporal bone and eustachian tube and inserts onto the palatine aponeurosis - elevates the soft palate
When the tensor veli palatini and levator veli palatini contract during swallowing, what do they cause to open?
During swallowing, contraction of the tensor and levator veli palatini cause the auditory tube to open due to their attachment to the cartilage of the auditory tube
- This allows the pressure between the middle ear and surrounding environment to equalise
What is the attachment and function of the palatopharyngeus and the palatoglossus?
- * Palatopharyngeus attaches from the palatine aponeurosis and the hard palate and inserts onto the posterior aspect of the lamina of the thyroid cartilage.
- It Tenses the soft palate and draws the pharynx anteriorly on swallowing
- * Palatoglossus attaches from the palatine aponeurosis to the tongue.
- It Elevates the tongue and depresses soft palate.
What is the attachment and function of the musculus uvulae?
Musculus uvulae attaches from the palatine aponeurosis and posterior nasal spine of the palatine bone and runs the length of the soft palate to insert into the mucous membrane of the uvulae Shortens the uvula
Restate the nerve supply to the muscles of the soft palate?
Tensor veli palatini - branch from the nerve to medial pterygoid which is a branch from the main trunk of CN V3
Levator veli palatini, palatopharyngeus, palatoglossus, musculus uvulae are all supplied by CN X in the pharyngeal plexus
We already know the majority of motor supply to the muscles of the soft palate comes from the vagus nerve Where does sensory innervation to the soft palate come from?
Sensory innervation to the soft palate from CN IX
Where do the greater, lesser and naso palatine nerves arise? What nerve travelling to provide paraysympathetics to lacrimal gland will enter this structure?
Greater, lesser and nasopalatine nerves arise from the pterygopalatine ganglion located in the pterygopalatine fossa
The greater petrosal branch of the facial nerve joins with the deep petrosal nerve (a sympathetic nerve) to form the nerve of the pterygoid canal which enters the pterygopalatine ganglion
What holds the sockets in the mandible open? (sockets for the teeth) What happens when this pressure is removed?
The sockets in the mandible are held open by the pressure of the teeth When these forces are removed, the alveolar bone will begin to fade until it is completely resorbed leaving a smooth mandible
How many adult teeth do you have? Name them?
32 adult teeth
- * 4 central incisors
- * 4 lateral incisors
- * 4 canines
- * 4 first premolars
- * 4 second premolars
- * 4 first molars
- * 4 second molars
- * 4 third molars (wisdom teeth)
What is the nerve supply to the teeth? (both upper and lower teeth)
Upper teeth are innervated by the anterior, posterior and middle branches of the superior alveolar nerve from V2
Lower teeth innervated by dental branches and incisive branch of the inferior alveolar nerve from CN V3
Inferior alveolar nerve - gives off dental branches, incisive branch and mental branch What does the inferior alveolar nerve run within? What does the mental branch innervate?
The inferior alveolar nerve runs within the mandibular canal giving off branches to the lower teeth
The mental nerve emergers from the mental foramen to innervate the skin of the chin and mucous membrane of the lower limp
