Week 2 - Oral cavity and Oropharynx Flashcards
Where is the vestibule?
Space between lips and cheeks superficially, and teeth and gingivae deeply
What muscle is innervated by facial nerve and lies in lateral wall of oral cavity?
Buccinator muscle
What muscle of facial expression causes closing and pursing of lips?
Orbicularis Oral - oral sphincter
What is the posterior opening to the oral cavity called?
Oropharyngeal
Which 2 bones form the hard palate?
Palatine process of maxilla
Horizontal plate of palatine bone
What are the muscles in the soft palate?
Tensor veli palatini
Levator veli palatini
Palatoglossus
Palatopharyngeous
Muscularis uvulae
What is the nerve innervation of the soft palate muscles?
Tensor veli palatini - medial pterygoid nerve which is branch of mandibular branch
All others are pharyngeal branch of vagus nerve
Where is the oropharynx?
Lie behind mouth and tongue
Anterior boundaries are left and right palatoglossal arches and extends to uvula of soft palate above to tip to epiglottis below
What are the important contents of oropharynx?
Palatine tonsils on lateral wall of each side
What are the functions of the tongue?
Moving food during chewing
Taste
Articulation
What is the foramen caecum?
Remnant of the proximal part of embryonic thyroglossal duct from which thyroid gland has developed
What are the surface projections of the mucus membrane of anterior third of tongue called?
Papillae
Filiform, Foliate and Vallate
Describe filiform
Long, numerous, thread-like
Contain central afferent nerve endings which are sensitive to touch
Describe foliate
Small lateral folds in lingual mucosa
Describe vallate
Large and flat topped projections
Which projection of the tongue mucosa does not contain taste buds?
Filiform type
What are the elevation of dorsal surface of posterior 1/3rd of tongue?
Lingual tonsils
What is the fold of the mucous membrane that fixes the tongue to the floor of mouth?
Frenulum
What vein can be seen on underneath of tongue?
Deep lingual vein
What is the sensory supply of the anterior 2/3 of tongue?
Lingual division of trigeminal nerve
What is the nerve which causes taste sensation in anterior 2/3rds of tongue?
Chorda tympani branch of the facial nerve
What is the sensory supply of the posterior 1/3rd of the tongue?
Glossopharyngeal nerve
What is the nerve that causes taste sensation of posterior 1/3rd of tongue?
Lingual branch of glossopharyngeal nerve
What are the 2 types of muscles of tongue?
Intrinsic - originate and insert within the tongue
Extrinsic - attach from tongue to surrounding bone or soft palate
What is the role of extrinsic and intrinsic muscles?
Extrinsic - Change position of tongue
Intrinsic - Affects shape and size of the tongue
What are the extrinsic muscles of the tongue?
Genioglossus
Hyoglossus
Styloglossus
Palatoglossus
Describe the genioglossus
Arises for mandibular symphysis
Protrudes tongue to opposite side
Describe the hyoglossus
Attaches to hyoid bone
Depresses tongue and helps shorten tongue
Describe the styloglossus
Attaches to anterior border of styloid process
Retrudes tongue and curls
Describe the palatoglossus
Attaches to soft palate
Can elevate posterior tongue or constrict isthmus
What is the innervation of the tongue muscles?
Hypoglossal nerve innervates all muscles of tongue
Except palatoglossus - vagus nerve
What are the 3 paired salivary glands?
Parotid
Submandibular
Sublingual
What are the 2 parts of the submandibular gland?
Superficial (inferior to muscle) and deep (superior to muscle)
What muscle separates the superficial and deep parts of submandibular gland?
Mylohyoid muscle
What artery grooves he under surface of the submandibular gland?
Facial artery
Where does the submandibular gland open into?
Oral cavity via submandibular duct
Where do ducts of sublingual gland lie?
In floor of mouth between mandible and genioglossus
What is the nerve innervation of parotid gland?
Glossopharyngeal nerve
What is the nerve innervation of the submandibular gland?
Facial nerve
What is the nerve innervation of the sublingual gland?
Facial nerve
Describe the larynx
Contains voice box and produces sound
Protective inlet of resp. system
Has supraglottis, glottis and subglottis
What does the larynx connect?
Mouth and trachea
Describe the paired and unpaired cartilages of the larynx
Unpaired - Hyoid bone, thyroid cartilage and cricoid cartilage
Paired - arytenoid, cuneiform and corniculate
What cartilage does the prominence of Adam’s apple in males sit on?
Thyroid cartilage
Which cartilage makes a complete ring shape?
Cricoid cartilage
What are the 2 dense connective tissue membranes between laryngeal cartilages?
Thyrohyoid ligament
Cricothyroid cartilage
What are the structures of the laryngeal inlet?
Epiglottis
Corniculate cartilage
Arytenoid cartilage
Inter-arytenoid fold
What 3 parts are the lumen of larynx split into?
1 - vestibule or upper part, area between laryngeal inlet and vestibular folds
2- middle part between vestibular folds and true vocal cords
3 - lower part extends from vocal cords to lower border of cricoid cartilage
Where does vocal fold and vestibular fold lie compared to each other?
Vestibular is more superior than vocal
What is the role of the intrinsic muscles of the larynx?
Control movement of vocal fold as well as controlling the diameter of the laryngeal inlet
Would would happen if the recurrent laryngeal nerve was transected?
Stridor and loss of voice
Obstruction of airway
What is the sensory nerve supply to the mucus membrane of the larynx?
Superior laryngeal nerve
Describe the vocal folds during normal resp., rapid breathing, and speaking
Normal - adducted
Rapid - abducted
Speaking - fully abducted
What are the 3 parts of the larynx?
Nasopharynx
Oropharynx
Laryngopharynx
What prevents the bolus entering the nasopharynx?
Soft palate
What are the 3 layers of the pharynx?
Outer muscular layer
Middle fibrous layer
Inner mucous layer
What is included in the outer muscular layer?
Outer circular layer and Inner longitudinal layer
What muscles are in outer circular layer?
3 constrictor muscles - superior, middle and inferior
Open in front at entries of nasal, buccal and laryngeal
What are the muscles of inner longitudinal lauer?
Stylopharyngeous - CN IX
Salpingopharyngeus - CNX
Palatopharyngeaous - CNX
What is the pharynx innervation?
Pharyngeal plexus
CNX, IX and sympathetic fibres
What is the sensory nerve of the pharynx?
CNIX - glossopharyngeal
What nerve provides most motor innervation of pharynx?
Vagus nerve
What is the role of the constrictor muscles during swallowing?
Propels bolus of food inferiorly to oesophagus
What is the role of the longitudinal layer of muscles in swallowing?
Elevate the larynx during swallowing
Shorten and widen pharynx
What is the purpose of the Weldeyer’s ring?
First line defence against microbes that enter body via nasal and oral cavities
What lymphatic collection are present in Weldeyer’s ring?
Pharyngeal tonsils
Palatine tonsils
Lingual tonsils
Tubal tonsils
