Lecture 9.2 Roof of oral cavity and surface anatomy

Question 1

What are the two parts of the roof of the oral cavity and what is it made of

Answer 1

1. Anteriorly = hard palate
   a) ant 3/4 made from palatine process of maxillae
   b) post 1/4 made from horizontal plates of the palatine bones
2. Posteriorly: Soft palate made of the palatine aponeurosis and 5 pairs of muscles:
   - Tensor Veli palatini
   - Levator Veli palatini
   - Palatopharyngeus
   - Palatoglossus
   - Musculus Uvulae

Question 2

What is the function of the hard palate vs the soft palate

Answer 2

Hard palate: palatine rugae on the anterior mucosa allow cleaning of the dorsal surface of the tongue.

Soft palate acts as a valve during the coordinated process of swallowing to prevent reflux of material into the nasopharynx

Question 3

What are the nerves and arteries on the roof of the mouth (soft palate and hard palate) and what are their exit and entries

Answer 3

Hard palate
Entering through Greater palatine foramen
1. Greater palatine artery -> incisive fossa
2. Greater palatine nerve-> doing posterior 3/4

Entering through Incisive fossa
1. Nasopalatine nerve-> doing anterior 1/4

Soft palate
Entering through Lesser palatine foramen
1. Lesser palatine artery, and nerve
-> doing the whole medial side

Also branches from … –> doing lateral side

• ascending palatine artery (from facial artery)
• palatine branch (from ascending pharyngeal artery)

Question 4

What is the structure and function of the Tensor veli palatini

Answer 4

1. vertical part coming from the base of the skull and cartilage of pharyngotympanic tube (muscular) on each side
2. connected at pterygoid hamulus (lower protrusion of the medial pterygoid plate) to Palatine Aponeurosis

Function: tense the soft palate and open the Eustachian tube

Question 5

What is the origin, insertion and function of the Levator veli palatini

Answer 5

Comes from the apex of the petrous temporal bone and eustachian tube. It goes down to insert on the palatine aponeurosis

Function: Pulls the soft palate up and back to shut off the nasopharynx

Question 6

What is the origin, insertion and function of the Palatopharyngeus

Answer 6

Originates from superior surface of palatine aponeurosis and hard palate adjacent.
Arches down posteriorly on the inner aspect of pharynx to thyroid cartilage.

Function
1. part of muscle fixed to hard palate elevates pharynx and larynx during swallowing

2. part attached to the aponeurosis helps to narrow the oropharyngeal isthmus

Question 7

What is the origin, insertion and function of Palatoglossus

Answer 7

Originates from inferior surface of palatine aponeurosis

Passes down in front of palatine tonsil to insert into side of tongue

Function: helps to narrow the oropharyngeal isthmus and elevate the tongue

Question 8

What is the origin, insertion and function of the Musculus Uvulae

Answer 8

Passes back from the hard palate and fuses with its counterpart to make the uvula

Function: elevate and retract the uvula helping levator veli palatini close the pharyngeal isthmus

Question 9

What is the innervation of the muscles of the soft palate

Answer 9

Pharyngeal plexus (CN10) except for Tensor vili palatini wqhich is CNV3

Question 10

What is the regions for lymphatic drainage of cancers of the oral cavity

Answer 10

region 1 and 2

Question 11

What structures should you be able to see on examination of the posterior oral cavity from anterior to posterior

(surface anatomy of the soft palate)

Answer 11

1. Lateral and anterior:
   Palatoglossal arches made from Palatoglossus
2. Palatine tonsil: lymphoid tissue, variation means not always seen
3. Medial and posterior: Palatopharyngeal arches made from palatopharyngeal muscle
4. In the middle is the Uvula
5. Posterior wall of the oropharynx

Question 12

What are the structures at risk when doing a tongue tie surgery/ tongue piercing, what are the consequences

Answer 12

Tongue tie is cutting the attachment at the base of the tongue

Can damage
- Lingual nerve, artery and vein which is running along the underside (ventral) of the tongue - (vein most visible).

Leads to numbness of the tongue, difficulty with speech. Too deep a cut can damage the genuhyoid for tongue tie.

Tongue piercing: also intrinsic muscles of tongue

Question 13

What is the lingual frenulum

Answer 13

Membrane that attaches the tongue to base of the oral cavity on the ventral surface

Question 14

If patient has oral ulcer what should you do

Answer 14

Examine the mouth, make sure its clean.

Even though 90% of oral ulcer is benign, if ulcer is there for 7 days+ it needs to go to specialist for biopsy to check for cancer. ENT surgeon can take it out.

Question 15

If patient has persistent bad breath what should you check for

Answer 15

Patent foramen caecum of tongue-left over from embryology period of thyroid growth food can get stuck there and make bad breath

Question 16

What is the structure of the Palatine Aponeurosis

Answer 16

Palatine Aponeurosis is fibrous lamellae attached to the posterior border of the hard palate. It fans out in a triangle over the posterior part of oral cavity and goes to the other vertical muscular part.

Receives attachment from all of the soft palate muscles