Muscles of Mastication Flashcards
Name the 4 main muscles of mastication.
Masseter m.
Temporalis m.
Lateral Pterygoid m.
Medial pterygoid m.
Name
Attachments
Innvervation
Masseter m.
Zygomatic region of zygomatic arch, Ramus and angle of mandible/coronoid process
Mandibular N (V3)
1st muscle to develop fully. Biting/clamping muscle. Bulges out when bites. Up and down motion Protraction “Moves forward”.
Masseter m.
Action
Blood supply
Innveration
Elevation and protraction of the mandible
Masseteric artery (Maxillary a./2nd portion)
Masseteric n. (CN V3 anterior division) (Nerve off mandibular n.)
Name
Attachments
General Innervation
Temporalis m.
Temporal fossa, Coronoid process/Anterior border of ramus
Mandibular n. (V3)
Temporalis M.
Action
Blood supply
Specific Innervation
Elevation and retraction of the mandible.
Anterior and posterior deep temporal arteries (vessels in temple) (Maxillary a./2nd portion)
Deep temporal nerves (CN V3)
Name
Attachments
Nerve broad
Lateral Pterygoid m.
Sup: Infratemporal surface of the sphenoid bone, Inf: Lateral surface of the lateral pterygoid plate, Condylar process of the mandible/articular disc of the temporomandibular joint.
Mandibular m. (V3)
Name this muscle group
Pterygoid muscles
Lateral Pterygoid Muscle
Action
Blood supply
Innervation
*Depresses mandible during chewing and speaking. Protrudes (a little bit). Side to side movement of mandible (Contraction pulls bone to ear, and jaw goes opposite direction.)
Pterygoid branches (Maxillary art)
Lateral pterygoid n. (CN V3)
Name
Attachments
Nerve
Medial Pterygoid m.
Pterygoid fossa/tuberosity of maxilla, Ramus and Angle of mandible
Mandibular n. (V3)
Medial pterygoid muscle
Action 3
Blood supply
Innervation
Elevates mandible, closes jaw, helps lateral ptyergoids in moving the jaw from side to side in contralateral direction.
Pterygoid branches of maxillary art.
Nerve to medial Pterygoid (CN V3)
Where does the stylomandibular ligament attach?
Purpose of ligament?
Styloid process and angle of mandible
Strengthens joint behind masseter.
At the temporal mandibular joint, what is the direction of the rotation of the jaw?
What happens if there is slack in the joint?
Rotates anteriorly
A little slack can disarticulate the mandible from the skull.
