Oral cavity and oropharynx Flashcards
Which bones form the structure of the roof of the mouth?
Maxilla (alveolar arch and palatine process)
Palatine bone (horizontal process)
What are the alveolar arches?
The part of the maxilla that the teeth are set in
How is the soft palate attached to the hard palate?
Hangs off horizontal process of palatine bone
Describe the structures which from the roof of the mouth?
Hard palate: alveolar arches, palatine process of maxilla, horizontal process of palatine bone
Soft palate
Which bones form the floor of the mouth?
Madible (deficient inferiorly)
Describe the muscles which form the floor of the mouth?
Mylohyoid muscle - diaphragmatic muscle, fills deficiency of mandible
Also digastric muscle and geniohyoid muscle
Describe the attachment of the geniohyoid muscle?
Mandible to hyoid bone
How is the tongue divided?
Divided into anterior 2/3 and posterior 1/3 by sulcus terminalis
What is the foramen caecum?
Depression in sulcus terminalis that is a remnant of duct from which thyroid gland develops
What are papillae?
Swellings on the tongue
Tastebuds embedded in their walls
Where are tastebuds located?
Embedded in the walls of the papillae
Describe the papillae of the tongue?
Valate papillae (directly anterior to sulcus)
Foliate papillae (posterolateral tongue)
Fungiform paillae (anterior 2/3 surface)
Which tonsils are associated with the tongue?
Lingual tonsils
Posterior 1/3 of tongue
Describe the extrinsic muscles of the tongue and their attachments and actions?
Palatoglossus: attaches to palate superiorly, elevates tongue
Styloglossus: attaches to styloid process posteriorly, retracts tongue
Hyoglossus: attaches to hyoid bone inferiorly, depresses tongue
Genioglossus: attaches to mandible in midline, protrudes tongue
Describe the innervation of the extrinsic tongue muscles?
All innervated by CN XII (hypoglossal) except palatoglossus, which is innervated by CN X (vagus)
Compare the functions of the intrinsic and extrinsic tongue muscles?
Intrinsic: alter shape of tongue
Extrinsic: alter position of tongue
When there is a lesion of the extrinsic tongue muscles, how will the tongue appear?
Deviates towards side of lesion on protusion
Describe the intrinsic muscles of the tongue?
Superior longitudinal
Inferior longitudinal
Transverse and vertical
Describe the innervation of the intrinsic tongue muscles?
CN XII (hypoglossal)
Describe the sensory innervation of the tongue?
ANTERIOR 2/3
Taste: chorda tympani (CN VII)
Sensation: lingual nerve (CN V, V3)
POSTERIOR 1/3
Taste and sensation: glossopharyngeal nerve
Describe the innervation of the teeth?
What is its significance?
Superior: superior alveolar nerve (branch of V2) - gives off posterior, anterior and middle
Inferior: inferior alveolar nerve (branch of V3)
Significance: pain referral between teeth and skin over face and ears
Briefly describe the different types of teeth?
Incisors (4 x2)
Canine (2 x2)
Premolars (4 x2)
Molars (6 x2)
Describe the pattern by which teeth are generally replaced?
From front to back
Describe the salivary glands in the oral cavity?
(Parotid gland outside oral cavity)
Sublingual gland: lateral to tongue in floor of mouth
Submandibular gland: wraps around mylohyoid; half below mylohyoid (outside oral cavity) and half above mylohyoid (inside oral cavity)
How does saliva from the parotid gland enter the oral cavity?
Via parotid duct, which travels anterior to masseter and opens opposite the upper second molar
How does saliva from the submandibular gland enter the oral cavity?
Duct of submandibular gland
Projects up to swelling just lateral to frenulum of tongue
Which neurovascular structures travel in the floor of the mouth?
Lingual arteries and veins
Hypoglossal nevre
Lingual nerve
Describe the arches present in the oral cavity and oropharynx?
Anterior: palatoglossal arch
Posterior: palatophrayngeal arch
Arches formed by folds of mucosa over underlying muscles of the same name
What landmark demaractes the back of the oral cavity and the oropharynx?
Back of alveolar arches
What are the arches of the oral cavity/oropharynx markers for?
Location of palatine tonsils
Tonsils located in between two arches
What is the function of the soft palate?
Selas off nasal cavity during coughing, swallowing, suction etc.
Helps seal oral cavity to allow unimpeded breathing during chewing
Describe the attachments of the musculus uvulae?
Connected to palatine aponeurosis, which is connected to palatine bone
Hangs in midline
Describe the 5 muscles associated with the soft palate, including their location and actions?
Tensor veli palatini: above, elevates
Levator veli palatini: above, elevates
Musculus uvulae: midline
Palatoglossus: below, depresses
Palatopharyngeus: below, depresses
Describe the innervation of the muscles associtaed with the soft palate?
All innnervated by pharyngeal branches of CN X, except tensor veli palatini, which is innervated by CN V
What is Waldeyer’s ring?
Incomplete ring of lymphoid tissue around oral and nasal cavities
Consists of pharyngeal, tubal, palatine and lingual tonsils
Describe the additonal actions of the levator muscles?
Closely related to auditory tube, so can contract to chnage its shape and assist with opening
