Muscles of facial expression
- Functions
- regulators of 3 openings
- eyes
- mouth
- nose
- Sphincters (circular), dilators (radial)
- Facial expressions: secondary effects of their contractions
- Supplied by
- 7th cranial nerve
- Developed from
- 2nd pharyngeal arch
- Represent panniculus carnosus
- Actions
- Frontalis
- look upwards without moving head
- Corrugator supercilii
- frowing
- vertical wrinkling of forehead
- Orbicularis oculi
- tight closure of eyes
- Dilators of mouth
- smile widely
- Buccinator
- puffing mouth
- blowing forcefully
- Facial expressions
- Smiling & laughing
- zygomaticus major
- Grinning
- risorius
- Sadness
- levator labii superiori
- levator anguli oris
- Grief
- depressor anguli oris
- Anger
- Dilator naris
- depressor septi
- Contempt
- zygomaticus minor
- Doubt
- mentalis
- Surprise
- Frontalis
- Horror & fright
- platysma
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Applied anatomy
- Bell’s palsy
- facial nerve paralysis
- Horner’s syndrome
- Tetanus
- Risus sardonicus
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Neck muscles
- Sternocleidomastoid & trapezius
- Nerve: Spinal accessory nerve
- torticollis
- wry neck
- Anterior triangle
- Suprahyoid muscles
- Digastric
- stylohyoid
- mylohyoid
- geniohyoid
- Infrahyoid muscles
- sternohyoid
- sternothyroid
- thyrohyoid
- omohyoid
- Posterior triangle
- splenius copitis
- scalenius anterior
- scalenius posterior
- scalenius medius
- inferior omohyoid
- levator scapulae
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Muscles of mastication
- Masseter
- Temporalis
- Medial pterygoid
- Lateral pterygoid
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Temporomandibular joint
- Synovial joint
- bicondylar variety
- Articular surfaces
- Articular eminence
- Mandibular fossa
- anterior part
- Head of mandible
- condyloid process
Movements
- Side-to-side
- chewing
- alternate contractions of medial & lateral pterygoids of opposite sides
- Protrusion/protraction
- simultaneous contraction of medial & lateral pterygoids of both sides
- Retrusion/retraction
- temporalis
- Elevation
- Masseter
- temporalis
- medial pterygoid
- Depression
- lateral pterygoid
- infrahyoid muscles
- gravity
Blood & nerve supply
- Blood supply
- Superficial temporal artery
- maxillary artery
- Nerve supply
- Mandibular nerve
- Auricotemporal nerve
- Masseteric nerve
Applied anatomy
- Jaw closed
- occlusal position
- stable position of joint
- Injury impact forces
- absorbed by teeth
- Dislocation of the head anteriorly into the infratemporal fossa
- Articular disc displacement