21. FIT Formula for Lifestyle
Physical Activity
• Most days of
the week
• Equal to brisk
walking
• About 150
kcal
• 3-5 METS
• Accumulate
30 minutes
22. - John Hughlings Jackson (1835-1911)
Father of English Neurology
Quoted by Stephen Porges 11/01
Social
Sympathetic
Parasympathetic
Freeze
23.
24. 24
A complex giniglymoarthrodial (hinge and glide)
articulation with limited capability of
diarthrosis (free movement)
Temporomandibular Joint (TMJ)
26. 26
Mandibular Condyle
• Modified barrel shape approx.
20 x 10 mm (ML x AP)
• Perpendicular to the
ascending ramus of mandible
• Dense cortical bone covered
with dense fibrous
connective tissue with
irregular cartilage like cell
27. 27
Mandibular Fossa
• Dense cortical bony surface
of temporal bone
• Posterior to articular
eminence
• Posterior nonarticular fossa
is formed by tempanic plate
• Thin at the roof of the fossa
and tympanic plate
29. 29
Articular Capsule
• Ligamentous capsule
surrounds the joint
• Attached to the neck of the
condyle and around the
border of the articular
surface of the temporal bone
• anterolateral aspect of the
capsule may thicken form
the Temporomandibular
ligament function as
stabilising structure
30. 30
Synovial tissue
• Synovial cell and connective tissue
covering the lower and upper-joint
spaces
• Synovial fluid, a proteoglycan-
hyaluronic acid complex acts as a
lubricant and may participated in
nutritional and metabolic interchange
for central part.
31. 31
Articular Disk (Meniscus)
• Biconcave oval structure
interposed between the
condyle and the temporal
bone
• 1 mm in the middle and 2-3
mm at periphery
• Dense collagenous
connective tissue
• Centre area is a vascular,
hyaine and devoid of nerve
32. 32
Articular Disk (Meniscus)
• Fuse to a strong
ligament at lateral side
connect to the neck of
the condyle
• The other borders are
attached to capsule
ligaments or synovial
membranes separate
between two joint
spaces.
37. 37
Functions of Ligaments
• Accessory ligaments may limit border
movements of the mandible
• Fibrous capsule and TM ligament may
limit of extreme lateral movements in
wide opening of mandible
39. 39
Masster muscle
• Superficial layer
– O : lower border of malar
bone, Zygomatic arch &
zygomatic process of maxilla
– R : Downward and
Backward
– I : Angle of mandible and
inferior half of the lateral
side of mandible
40. 40
Masster muscle
• Deep layer
– O : Internal surface of
zygomatic arch
– R : Downward (vertical)
– I : Ramus of mandible and
base of coronoid process
– 50 degree between 2 layers
41. 41
Temporalis muscle
• 3 bundles
– Anterior bundle (vertical fibre)
–Action: Mandible elevator (Close
jaws), crushing and chewing at
C.O.
–Inaction: Mandible depression
(except Max. Opening and Opening
against resistance)
42. 42
Temporalis muscle
– Posterior bundle (Horizontal
bundle)
Action: Mand. retraction and
positioner
Inaction: Mand. depression and
protrusion
– Intermediate bundle
Action: Protrisive movement
– Nerve supply
Ant. and Post. deep
temporal nerve
43. 43
Med. Pterygoid muscle
O : Pterygoid fossa and medial
surf. of the lateral pterygoid
plate
I : Inf. + Post. border of ramus
and angle of mand.
R : Downward and Backward
N : Medial Pterygoid nerve
Rectangular shape at medial surface of ramus,
synergistic with masseter muscle
44. 44
Lat. Pterygoid muscle
• Superior head
O: Wing of sphenoid and
infratemporal crest
R: Downward and Backward
• Inferior head
O: Lateral surf. of lateral
pterygoid plate
R: Upward and backward
45. 45
Lat. Pterygoid muscle
Insertion of superior and inferior
heads
– Ant. portion of the condylar neck
(pterygoid fovea)
– Ant. surface of the articular
capsule
– Ant. Border of the disk
Function
– Open the jaws, protrude and
lateral movement with moving
disk forward
46. 46
Lat. Pterygoid muscle
• Superior head
Synergistic with elevator
group of muscle for closing
and clenching
• Inferior head
Synergistic with suprahyoid
group of muscle for opening
jaw
• Nerve supply
Lateral pterygoid nerve
49. 49
Types of Mandibular Movement
• Rotational movement
– Horizontal axis of rotation
– Frontal (vertical) axis of rotation
– Sagittal axis of rotation
• Translational movement
55. 55
Sagittal Plane Border Movement
• Posterior open border
• Anterior open border
• Superior contact border
• Functional movements
56. 56
Horizontal Plane Border Movement
• Left lateral border
• Continued left lateral border
with protrusion
• Right lateral border
• Continued right lateral border
with protrusion
• Functional movements
63. Internal Derangements
General orthopedic term implying a mechanical fault
that interferes with the smooth action of a joint
The most common internal derangement is disc
displacement
Clinical Features
Clicking sounds from joint(s)
Restricted or normal mouth opening capacity
Deviation on opening
Pain
64. Imaging Features
Anterior disc displacement: posterior band of the
disc located anterior to the superior portion of
the condyle at closed mouth on oblique sagittal
images
Disc may have normal (biconcave) or deformed
morphology
In opened mouth position disc may be in a
normal position (“with reduction”) or continue to
be displaced (“without reduction”)
Internal Derangements
65. Osteoarthritis
Definition
Non-inflammatory focal degenerative disorder of
synovial joints, primarily affecting articular cartilage and
sub-condylar bone; initiated by deterioration of articular
soft-tissue cover and exposure of bone.
Clinical Features
Crepitation sounds from joint(s)
Restricted or normal mouth opening capacity
Pain or no pain from joint areas and/or of mastication
muscles
Occasionally, joints may show inflammatory signs
Women more frequent than men
66. Arthritides
Definition
Inflammation of synovial membrane characterized by
edema, cellular accumulation, and synovial proliferation
(villous formation).
Clinical Features
Swelling of joint area, not frequently seen inTMJ
Pain (in active disease) from joints
Restricted mouth opening capacity
Morning stiffness, in particular stiff neck
Dental occlusion problems; “my bite doesn’t fit”
Crepitation due to secondary osteoarthritis
