Oral cavity, pharynx and larynx

Question 1

Name the muscles of the soft palate

Answer 1

• Levator veli palatini
• Tensor veli palatini
• Palatoglossus
• Musculus uvula

Question 2

1. How many perminant teeth are there?
2. What is the name of the chart they are recoreded on?
3. What is the minimum interdental distance in young adults?

Answer 2

1. 32
2. Palmar notification chart
3. 37mm

Question 3

1. What does the mucosa comprise of?
2. Name the intrisic muscles of the tongue
3. Name the extrisic muscles of the tongue

Answer 3

1. Papillae and lymphoid tissue (lingual tonsils)

2.

• Inferior longitundinal
• Superior longitudinal
• Transverse
• Vertical muscles

3.

• Genioglossus
• Hypoglossus
• Styloglossus
• Palatoglossus

Question 4

1. Motor innervation of the tongue
2. Sensory innervation
3. Secretory function

Answer 4

1. Motor= hypoglossal n (CNXII)

except palatoglossus (vagal X)

2. Sensory=

• Anterior 2/3=
  
  • lingual branch of V3- general sensation
  • Taste Chorda tympani from CN VII (facial)
• Posterior 1/3
  
  • Generalised sensation and taste glossopharyngeal (IX)

3. Chorda tympani of facial (CNVII)

Question 5

Name the muscles and salivary glands in the floor of the mouth

Answer 5

• Sublingual and submandibular salivary glands
• Digastric and stylohyoid
• Mylohyoid

Question 6

1. Describe the structure of the pharnyx and name the muscles

Answer 6

• It is a FIBROMUSCULAR tube with
  
  • external circular muscles:
    
    • Superior constrictors
    • Middle constrictors
    • Inferior contrictors
  • Longitudinal inner
    
    • Stylopharyngeus
    • Palatopharyngeus
    • Salpingopharyngeous

Question 7

Name the different areas of the pharnyx and define their boarders

• Why are the tissues of the laryngopharynx friable

Answer 7

Nasopharynx

• lies posterior to the nasal choana
• Superior to the soft palate

Oropharynx

• Superior boarder is soft palate
• Inferior boarder is base of tongue
• Lat walls are palatopharyngeal arches with palatine tonsils

Laryngopharynx

• Posterior to the larynx
• Extends from superior border of epiglotis to cricoid
• Posterior and lateral wall made of constricter muscles
• Communicated with the larynx via the laryngeal inlet, piriform recesses are parallel to this
• Friable due to lack of serosal layer and few supporting structures, perforation of the pharynx and oespohagus can lead to mediastinitis which has a poor outcome

Question 8

1. What is the motor innervation of the pharynx
2. What is the sensory innervation of the pharynx
3. Describe the gag reflex

Answer 8

1. Motor: Pharyngeal branches of accessory nerve run alongside the vagus
2. Sensory: pharngeal branches of CN IX (Glossopharyngeal), except nasopharynx CNV2
3. Gag reflex: prevents noxious material going into the pharynx or trachea following stimulation of the soft palate or posterior tongue the is a reflex contraction of soft palate
   - sensory innervation by CNIX motor by vagus

Question 9

1. Function
2. Cartilages
3. Ligaments
4. Why is the cricothyroid membrane used for cricothyroidotomy?

Answer 9

1.

• Valve that protects the tracheobronchial tree
• Phonation

2.

• Thyroid
• Cricoid
• Arytenoids (x2)
• Corriculate (x2)
• Cuneifrom (x2)
• Epiglottic

3.

• Thyrohyoid
• Cricothyroid

4. used because it is easily palpable and a complete ring. This space will allow a 6cm ET to be inserted through it.

Question 10

1. Name the extrinsic muscles and their functions
2. Name the Intrinsic muscles and their functions

Answer 10

1. Extrinsic:

• Infrahyoid depresses hyoid and larynx
• suprahyoid elevates hyoid and larynx

2. Intrinsic: alter the lenght and tension of vocal folds

• Cricothyroid
• Cricoarytenoideus
• Arytenoideus
• Aryepiglotticus
• Thyroarytenoideus
• Thyroepiglotticus

Question 11

1. Describe the innervation of the larynx
2. Describe the effects of lessions on these nerves

Answer 11

1. Vagus n. via

• Superior laryngeal n (SLN)
  
  • Internal Laryngeal nerve (sensory)
  • External Laryngeal n. (Motor)
• Recurrent Laryngeal n. (RLN)
  
  • Runs between oesophagus and trachea over medial aspect of the thyroid
  • Vulnerable during thyroidectomy, carotid endartectomy and surgery to anterior neck
  • Supplies motor for all intrinsic musclesexcept cricothyroid and sensation

2.

RLN:

• Unilateral palsy= horseness and weak cough
• Bilateral palsy= can cause airway obstruction and/ or hoarseness

SLN: horseness