Transcript TMJ, Face, Skull

TMJ, Face, Skull
TMJ
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Mandibular fossa of temporal bone with
condyle of mandible
Incongruent surfaces
Two joint cavities with articular disc
interposed
Lower cavity = hinge joint
Upper joint = gliding
TMJ
TMJ
Mandible
Mandible
TMJ
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Capsule
• Surrounds the joint
• Encloses the disc
• Attaches above the margins of the mandibular
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fossa
To the neck of the mandible
Inner aspect of capsule attaches to disc
Above disc – capsule loose
Below disc - taut
TMJ Capsule
TMJ Capsule
TMJ
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Ligaments
Lateral ligament - AKA TMJ ligament
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From zygomatic bone to run inferiorly and posteriorly to
blend with the joint capsule to attach to lateral and posterior
parts of the neck of the mandible
Sphenomandibular
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Strong thin flat band lying on medial aspect of the joint
Passes inferiorly and forwards from the spine of the
sphenoid to the lingula
Stylomandibular
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Extends from the apex of the styloid process to the lower
part of the posterior border of the ramus of the mandible,
near the angle
TMJ Capsule
TMJ
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Innervated by CN V, Mandibular branch
Movements
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Elevation, depression, retraction, protraction, side to side
Elevation and depression involves the hinge like
rotation of the condyle against the disc in the lower
compartment
Protraction and retraction – actions whereby the
condyle and disc move as one unit against the
mandibular fossa. In protraction the condyle and disc
glide forwards so that the condyle rides on the
articular eminence – retraction = opposite
CN V Trigeminal
TMJ Motions
TMJ Motions
TMJ
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Side to side – grinding movements
• Mandible is alternately protracted and
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retracted with the two sides moving in
opposite directions so that one side is
protracted while the other is retracted
Actions combined with elevation and
depression, rhythmically and alternately
Muscles of Mastication
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Masseter
Temporalis
Lateral pterygoid
Medial pterygoid
All innervated by CNV
Opening of jaw (depression) primarily
passive or gravity assist
Masseter
Temporalis
Pterygoids
Pterygoids
Pterygoids
Nerve Supply to Face
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Sensory by three divisions of CN V –
opthalmic, maxillary, mandibular
Innervation of muscles of facial carried
out by CN VII – the Facial Nerve
Origin, branches, motor functions,
sensory functions, parasympatheric
functions
CN V
CN V
Sensory to Face
Sensory
Scalp
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Three Layers
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Outer = skin
Beneath that – subcutaneous layer with many nerves
and vessels running through here, binds skin to inner
layer
Galea Aponeurotica – AKA epicranial aponeurosis
Galea attaches to pericranium via loose CT
This allows scalp to move over the skull
Most muscles of face attach to skin, this
arrangement allows them to be more mobile.
Scalp
Scalp
CN VII – The Facial Nerve
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Motor nerve to muscles of facial
expression with one notable exception
Origin = lower pons
Branches – common nerve enters face
• Temporal
• Zygomatic
• Buccal
• Mandibular
• Cervical
Motor to Face CNVII
CN VII
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Motor Functions
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Sensory functions
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Parasympathetic
• Muscles of facial expression
• External ear
• Ant. 2/3 of tongue
• Soft palate
• Pharynx
• Gland stimulation
CN VII
Muscles of Facial Expression
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Primary action is to act as either a sphincter or
dilator of the orifices of the face
Facial expression is a by-product
Orifices
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Lips = labia
Nose = nares; Nostrils, Septum, Ala, Apex, Root
Eyelids = palpebrae
External Ear = auricle, lobule = soft portion
Selected Muscles of Facial
Expression * = learn
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Orbicularis Oculi
Levator Palpebrae Superioris*
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O: Root of Orbital Cavity
I: Skin of upper eyelid
A: Raises upper eyelid
N: Note Well, Nerve = CN III
Ptosis is a condition of denervation to this
muscle causing drooping of the eyelid, a
clinical symptom indicating more loss
Facial MM
Facial MM
Facial MM
Facial MM
Muscles Continued
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Occipitofrontalis
Corrugator
Auricular muscles of the ear – ant., post.,
sup.
Nose
• Nasalis
• Procerus
• Depressor Septi
Facial MM
Facial MM
Ear MM
Nose MM
Nose MM
Muscles
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Mouth
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Depressor anguli oris
Depressor labii inferior
Mentalis
Risorius
Orbicularis oris
Buccinator*
Zygomaticus major
Zygomaticus minor
Levator labii superioris
Platysma
Platysma
Mouth
Facial MM
Extra Occular Muscles of the
Eye
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Muscles that move the eyeball
Innervated by: CN III (most), CN IV
(1),CN VI (1)
Many have an origin from the annulus
tendinous, a common tendon ring
attached around the optic canal
Most attach to the sclera of the eyeball
Eye MM
Muscles *
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Superior Rectus – rotates eyeball
upward and medially –CN III
Medial Rectus – rotates medially (ADD)
– CN III
Lateral Rectus – rotates eyeball laterally
(ABD) – CN VI
Inferior Rectus – rotates eyeball
downward and medially – CN III
Eye MM
Eye MM
Eye MM
Eye MM
Muscles *
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Superior Oblique – rotates eyeball downward and
lateral – CN IV
Inferior Oblique – rotates eyeball upward and lateral
– CN III
Combined motions
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Up and medial = sup.rectus
Up and lateral = inferior oblique
Straight up = sup. rectus and inf. oblique
Straight down = inf. rectus and sup. oblique
Down and medial = inferior rectus
Down and lateral = superior oblique
Lateral Gaze = ABD of one eye with ADD of the other
Eye Movements
Eye Movments
Eye Movements