Throat Anatomy and Physiology Flashcards
What are the 2 parts of the oral cavity?
–Oral vestibule (between lips and teeth)
–Oral cavity proper
What are the boundaries of the oral cavity?
–Lips to palatoglossal arch (anterior pillar)
–Palate to floor of mouth/tongue
–Buccal mucosa
Where is the parotid gland placed?
The duct pierces the buccinator muscle, then opening up into the oral cavity on the inner surface of the cheek, usually opposite the maxillary second molar.
Where is the submandibular gland placed?
Lying superior to the digastric muscle, each submandibular gland is divided into superficial and deep lobes, which are separated by the mylohyoid muscle.
What does the lingual nerve supply?
Sensory innervation from the anterior two-thirds of the tongue
Where does the lingual nerve come from?
The lingual nerve is a branch of the mandibular division of the trigeminal nerve. It also carries nerve fibers that are not part of the trigeminal nerve, including the chorda tympani nerve of the facial nerve, which provides special sensation (taste) to the anterior 2/3 part of the tongue
What are the functions of the oral cavity?
Taste
Mastication
- Teeth, tongue
Speech
- Tongue, cheek, lips
Digestion
- Salivary enzymes
Swallowing
- Tongue, hard and soft palate
What is the posterior 1 third of the tongue supplied by?
Supplied by CN 1X
What are the most common papillae on the tongue?
Filliform papillae are the most numerous bu do not contain taste buds
What is the effect of the intrinsic and extrinsic muscles of the tongue?
- Intrinsic muscles (alter shape)
- Extrinsic muscles (alter position)
What are the extrinsic muscles of the tongue?
Genioglossus, styloglossus, hyoglossus and palatoglossus.
GP Harry Styles
What is the nerve supply for the muscles of the tongue?
CN XII: hypoglossal nerve supply all except for palatoglossus – pharyngeal plexus (CN IX - X)
What are the 4 muscles of mastication?
- Lateral pterygoid
- Medial pterygoid
- Temporalis
- Masseter
What is the nerve supply for the muscles of mastication?
•CN V3
What are the boundaries of the oropharynx?
- Lower border of soft palate to upper margin of epiglottis
- Palatoglossal arch to posterior pharyngeal wall
- Lateral: faucial pillars & palatine tonsils
What is the epithelium of the oropharynx?
•Stratified, non-keratinised squamous
What is the nerve supply of the oropharynx?
•Pharyngeal plexus- CN IX & X
What is the blood supply of the hypopharynx?
Superior Thyroid Artery, the Lingual Artery and the Ascending Pharyngeal Artery.
What is the nerve supply of the hypopharynx?
Nerve supply is from the pharyngeal plexus.
What are the boundaries of the hypopharynx?
- Superior margin of epiglottis to lower border of cricoid cartilage
- Continuous with oesophagus
- Anterior wall: back of larynx
What are the three subsites of the hypopharynx?
- Pyriform sinus
- Post-cricoid area
- Posterior pharyngeal wall
What are the three phases of swalowing?
Oral phase
Pharyngeal
Oesophageal
What happens during the oral phase of swallowing?
- Tongue propels food (bolus) into pharynx
- Triggering swallowing reflex (afferent: CN V, IX, X – swallowing centre in medulla – efferent: CN VII, X, XII)
What happens during the pharyngeal phase of swallowing?
- Soft palate pulled upwards
- Epiglottis covers the larynx, vocal cord approximate, larynx moves upward
- Upper oesophageal sphincter (UOS) relaxes
- Respiration is reflex inhibited
What is the oesophageal phase of swallowing?
- Once bolus passed UOS, the sphinter constricts
- Bolus propelled downwards by peristaltic motion, reflex via myenteric plexus
What is the function of the larynx?
–Part of respiratory tract
–Voice
–Swallowing
What are the three parts of the larynx?
Supraglottis
Glottis
Subglottic
What are the major cartilages of the larynx?
What is the motor innervation of the larynx?
All intrinsic mucles supplied by recurrent laryngeal nerve except for cricothyroid muscle (external laryngeal nerve)
What is the sensory innervation of the larynx?
Supraglottic: internal laryngeal nerve
Glottic and subglottic: recurrent laryngeal nerve
Why does the left recurrent laryngeal nerve have a higher chance of injury during a chest operation?
The left recurrent laryngeal nerve has a longer course since it loops around the aortic arch instead of the right subclavian artery and therefore has a higher risk of injury during operative chest procedures
What are the 5 portions of speech?
Respiration
Phonation
Resonation
Articulation
Prosody
What is phonation?
Flow of air through different vocal chord positions, tension and length
What is resonation?
- Oral/nasal speech balance
- Depend on nasopharynx, nasal cavity & oral cavity
What is articulation?
•Production of speech , determined by action of lips, tongue and jaw
Define prosody
- Production of syllable stress and emphasis
- Provide effective speech tone
