TMJ and masseteric muscles Flashcards
Identify these muscles
Action? Innervation?
- Masseter (deep head)
- Masseter (superficial head)
- > action - elevates mandible
- > nerve - Masseteric n. from mandibular division of trigeminal n.
Identify
Action? Nerve?
- Temporalis
A - Elevates mandible; Retrudes mandible (posterior fibers)
N - Anterior and posterior deep temporal nn. from mandibular division of trigeminal n.
What is the Main postural muscle that maintains mandible in rest position?
Temporalis
Identify. Actions? Innervation?
- Superior head of the lateral pterygoid m.
- Inferior head of the lateral pterygoid m.
Actions:
Depresses mandible
Protrudes mandible
Lateral excursion of mandible
Nerve: Lateral pterygoid branches (for each head) of mandibular division of trigeminal
Identify. Actions? Innervation?
- Deep head of the medial pterygoid m.
- Superficial head of the medial pterygoid m.
Actions:
Elevates mandible
Protrudes mandible
Lateral excursion of mandible
Nerve: Lateral pterygoid branches (for each head) of mandibular division of trigeminal
What is the deepest muscle of mastication?
medial pterygoid m.
Where do the arteries of muscles of mastication arise from?
2nd part of the maxillary a. (pterygoid part).
Arteries of the Muscles of Mastication
- Masseteric a.
- Posterior deep temporal a.
- Anterior deep temporal a.
- Lateral pterygoid a.
- Buccal a.
- Medial pterygoid a.
- External carotid a.
- Maxillary a.
The nerves that supply the muscles of mastication arise from the ___
mandibular division of the trigeminal n
Nerves of the Muscles of Mastication
Identify 1 - 4
- Chorda tympani n.
- Auriculotemporal n.
- Mandibular n.
- Posterior deep temporal n.
Nerves of the Muscles of Mastication
Identify 5 - 8
- Anterior deep temporal n.
- Masseteric n. (cut)
- Lateral pterygoid n.
- Buccal n.
the mandibular division of the trigeminal n.
-> After passing through the foramen (1)___ within the (2)___ fossa, the mandibular division divides into (3)___ and (4)___ divisions.
1 - ovale
2 - infratemporal
3 - anterior
4 - posterior
Compartments of the Temporomandibular Joint
Identify 6 - 8
- Retrodiscal pad
- Superior lamina
- Articular disc
Joint type of TMJ
a ginglymoarthrodial joint because it has hinge and sliding movements
Veins of the Temporomandibular Joint
- Pterygoid plexus
- Maxillary v.
- External jugular v.
- Posterior retromandibular v.
- Retromandibular v.
- Posterior auricular v.
- Transverse facial v.
- Superficial temporal v.
Course of superficial temporal vein
Receives some branches from TMJ
Joins maxillary v. to form retromandibular v.
Course of maxillary vein
Receives some branches from TMJ
Joins superficial temporal v. to form retromandibular v.
Sensory Nerves of the Temporomandibular Joint
- Otic ganglion
- Masseteric n.
- Auriculotemporal n.
- Inferior alveolar n.
- Lingual n.
- Nerve to the mylohyoid
Course of Auriculotemporal nerve
From posterior division of mandibular division of trigeminal n.
- > Supplies sensory branches all along capsule
- > carries autonomic function to parotid gland
What is the condition being depicted in the last image?
Dislocation of the Mandible
-> Mandibular dislocation occurs when the condyle moves anterior to the articular eminence.
Source of Masseteric nerve
Anterior division of mandibular division of trigeminal n.
Source of Posterior deep temporal nerve
Anterior division of mandibular division of trigeminal n.