Oral Cavity, Tongue And Pharynx Flashcards
What are the 4 walls of the Oral cavity?
2 lateral walls
Floor
Roof
What forms the Lateral walls of the oral cavity?
Buccinator muscles
What makes up the roof of the oral cavity?
What makes up the floor?
Hard and soft palates
- Various muscles (Including 2 Mylohyoid muscles)
- Tongue + other soft tissues
State the Anterior and Posterior boundaries of the oral cavity
- Begins anteriorly at the Oral Fissure (Bounded by lips)
- Extends posteriorly to the Oropharyngeal isthmus
What is the Oropharyngeal Isthmus?
An arch formed by the Soft Palate superiorly and the Dorsum of the Tongue Inferiorly
What 2 structures make up the sides of the Oropharyngeal Isthmus?
What muscles make up these structures?
- Palatoglossal Arch/ Pillar/ Anterior pillar of Fauces
- Palatoglossal muscle
- Palatopharyngeal Arch/ Pillar/ Posterior pillar of Fauces
- Platopharyngeal muscle
What is found between the Palatoglossal and Palatopharyngeal Arches?
What does the Oropharyngeal Isthmus continue posteriorly into?
Tonsillar Fossa, within which are the Palatine tonsils
The Oropharynx
The Palatoglossus and Palatopharyngeal muscles run from Soft Palate to Tongue and Pharynx.
State their action
Pulls soft palate down towards back of the tongue, closing the Oropharyngeal Isthmus, ensuring food stays in oral cavity when chewing
The tongue is entirely muscular and is covered in mucous membrane.
Describe the Intrinisc muscles
Intrinsic;
- 4 paired muscles
- Motor innervation via CN XII
- Blend with Extrinsic muscles , no bone attachments
In what directions do the Intrinisc tongue muscles run?
What do they act to do?
Run Vertically, Longitudinally and Transversely
Act to alter the tongue shape
List the 4 Extrinisic tongue muscles and state their innervation
(Arise from other structures and insert into tongue)
What do these muscles act to do?
- Styloglossus, CN XII
- Genioglossus, CN XII
- Hyoglossus, CN XII
- Palatoglossus, CN X
Act to change the position of the tongue (Protraction, side to side)
What is the most clinically important Extrinsic tongue muscle and why?
- Genioglossus
- Acts to protrude the tongue
- Used to test CN XII function
Which nerve fibres supply Special sensory innervation to the Posterior 1/3 and Anterior 2/3 of the tongue
Anterior 2/3: Chorda Tympani branch of CN VII
Posterior 1/3: CN IX
Which nerve fibres supply General sensory innervation to the Posterior 1/3 and Anterior 2/3 of the tongue
Anterior 2/3: Lingual branch of Vc
Posterior 2/3: CN IX
What glands are associated with the Wharton’s and Stensen Ducts
Wharton’s: Submandibular (60% of saliva)
Stensen: Parotid
(Sublingual has multiple ducts)
Which nerves make up the Afferent and Efferent limbs of the Gag Reflex
Afferent: CN IX
Efferent: CN X
Describe how Uvula position can be used to asses CN X Lesion
- Patient opens mouth and says ‘ahh’
- If CN X Lesion is present, Uvula deviates to Contralateral side of weakness
How can Uvula position differ in Tonsilitis and Peritonsilalr Abscess
PT Abscess;
- Uvula pushed aside/ deviated
Tonsillitis;
- Central uvula
How many a Peritonsillar abscess present?
Suggest 2 causes
- Fever
- Bad breath
- Drooling
- Hard to open mouth
- Can follow on from untreated/ partially treated tonsillitis
- Can be due to bacterial infection
What is the Pharynx?
List its 3 parts
A muscular tube from Base of Skull to C6, whose superior part lies posterior to Nasal and Oral cavities
- Nasopharynx
- Oropharynx
- Laryngopharynx
What covers the posterior wall of the Pharynx?
Buccopharyngeal fascia
This lies against the Prevertebral fascia, forming the Retropharyngeal space
The Nasopharynx lies superior the Soft Palate.
Through what holes/ openings does do nasal cavities open into the Nasopharynx
2 Posterior Nasal apertures (Choanae)
Which Cervical vertebrae lie posterior to the Nasopharynx
Name 2 structures found in the Nasopharynx
C1, C2
- Pharyngeal tonsil/ Adenoids
- Orifice of Eustachian tube
The Adenoids are prominent in children, but atrophy after puberty.
What can Adenoid enlargement lead to?
What are 4 signs/ symptoms/ complications?
- Blockage of Eustachian tube
- Blockage of airflow through Choanae
- Snoring/ sleep apnea
- Mouth breathing + Nasal tone to voice
- Chronic sinusitis (sore throat)
- Middle ear infections (or OM with Effusion)
