lecture 2 Flashcards
What is special about the mandibular division of the trigemnal nerve?
It contains both sensory and motor nerve fibres.
Where does the sensory component of the mandibular division arise from?
From the inferior aspect of the trigeminal ganglion
Where does the inferior aspect of the trigeminal ganglion exit the cranial cavity from?
Exits the cranial cavity almost immediately through foramen ovale
What does the inferior aspect of the trigeminal ganglion give rise to?
The sensory component of the mandibular division
When do the sensory and motor components fuse together?
Immediately after emerging from the foramen into the infratemporal fossa.
What does the infratemporal fossa contain?
- Several of the muscles of mastication
- The maxillary artery and its branches
- The pterygoid plexus of veins
- The mandibular nerve
What is the pterygoid plexus of veins a route for?
It is a route for transmitting infection into the cranial
cavity
What happens if an infection spreads into the infra temporal fossa?
The infection can spread to other sites through the fossa’s communication with several spaces in your head.
The spread of infections between the ‘spaces’ of the head can lead to serious, even fatal conditions.
Where can infections of the infratemporal fossa originate?
Such infections can originate in the dental tissues or be introduced during dental procedures.
What does the infratemporal fossa communicate with medially?
Communicates medially with the pterygopalatine fossa
Where is the pterygopalatine fossa located?
positioned posterior to the maxilla
What forms the lateral boundary of the infratemporal fossa?
the ramus of the mandible
What is the infratemporal fossa continuous with superiorly?
Superiorly, it is continuous with the temporal fossa at the level of the zygomatic arch
Name one of the initial branches of the mandibular nerve
The nerve to medial pterygoid
What does the nerve to medial pterygoid supply?
Supplies the medial pterygoid muscl
What happens to the maxillary nerve after it has given off the nerve to medial pterygoid and another small nerve?
he mandibular nerve splits into two parts:
- Anterior trunk
- Posterior trunk
Describe the nerve fibres found in the anterior trunk
It is mainly motor with one sensory branch
Describe the nerve fibres found in the posterior trunk
It is mainly sensory with one motor branch
Which trunk is smaller the posterior or anterior trunk?
The anterior trunk
What does the anterior trunk supply?
Supplies the:
temporalis
lateral pterygoid
masseter muscles
What is the sensory branch of the anterior trunk called?
The long buccal nerve
Where does the long buccal nerve run?
It travels anterolaterally, passing anterior to the ramus of the mandible.
What does the ling buccal nerve supply?
the buccal gingivae adjacent to the mandibular molars
When must the ling buccal nerve be anaesthetised?
When mandibular molars need to be extracted
What does a long buccal block anaesthetise?
anaesthetises the long buccal nerve as it passes anterior to the mandibular ramus.
How many branches does the posterior trunk have?
It has three large branches
They are mainly sensory
Name the 3 branches of the posterior trunk
- The Auriculotemporal Nerve
- The Lingual Nerve
- The Inferior Alveolar Nerve
Describe the nerve fibres in the Auriculotemporal Nerve?
It is entirely sensory
What is unusual about the configuration of the first part of the Auriculotemporal Nerve?
It splits into two branches that run on either side of the middle meningeal artery
When do the 2 branches of the first part of the Auriculotemporal Nerve reunite?
on the other side of the middle meningeal artery